Star12

Very much depends on the State, a few will require the NOA, most it seems the next thing you get will be the EAD.

Hello-  the bio page of the passport is not sufficient if you want to avoid RFE.
 
Please copy all pages of your passport including front and back cover of the passport.

No, don't.  Not safe, not necessary.  The consulate where he interviews should be familiar with the concept of unobtainable police certs, even if not specifically Sudan.  Like payxibka mentioned, you can print out the document attesting to this.  Best wishes.

This is a great topic. Thank you IlyaM for bringing this topic up here. All the best of luck to you, I don't think you should have issues. 
 
My fiance and I have been researching what to provide for "unobtainable" police certificates. On the reciprocity schedule for Sudan, police certificates are available for those that are PRESENT IN SUDAN.  
https://travel.state.gov/content/travel/en/us-visas/Visa-Reciprocity-and-Civil-Documents-by-Country.html
 
My fiance lived in Sudan for 1 year (April 2018 - April 2019), and due to the civil unrest in Sudan, he left for his safety to Uganda. He left not too long after the airways opened up again in Sudan, and commercial airlines began to come back.   
 
Coincidentally, in May I submitted my fiance's signed Change of Address declaration to USCIS with our RFE that stated he moved for safety reasons because of Sudan's volatile climate. 
 
Now (Sep 2019), Sudan is in a transitional government, and I think it's unwise for him to return because in Africa you never know if things are truly stable. Also we feel that the Consular Officer might think of it as a red flag if he does return to Sudan after his declaration stating that he felt unsafe there in April.  
 
My fiance has his police certificate from the country of his nationality and also is planning to get one in Uganda too for good measure.  Should we write up a Declaration/Affidavit letter for why my fiance could not obtain his Sudan police certificate and have it notarized in Uganda? Somewhat as a substitute for the police certificate?

Many countries will not issue a police certificate to non-residents.  Sudan appears to be one of those countries. 
 

They should but doesn't mean you shouldn't be prepared 

If you want peace of mind,  bring a printout of the appropriate section of the website that states that it is unobtainable 

You dont have to write anything when the police certificate is listed as unobtainable.    

Another thought, and hopefully the CO at your interview would see it the same way, on your previous stays you couldn't get a police clearance for, in reality if you had had any criminal actions against you I believe they wouldn't give you a work permit, let alone let you back in the country depending on what you did. And the fact that you have something, and you made your best effort to get everything, I would think you would be ok. Hope everything works out for you as it seems you have done your due diligence and are trying to cover all your bases.

@Greenbaum
Yeah, i've read all this information. Huge thanks. I'm still hoping that I won't be given the 221g refusal at the interview because of my police clearance certificate not covering the whole stay in China. What really weird is that I can't even find a proof that the certificate for my first visas is unobtainable cos the PSB doesn't give this kind of paper. Local police station and the notary office dont provide anything like that either. So let's hope for the best and thanks for your help again

Here is some information that I have for countries outside of China and for China. I am not familiar with china so this is about all I can do to help. Have you been to this website for additional instructions? https://travel.state.gov/content/travel/en/us-visas/Visa-Reciprocity-and-Civil-Documents-by-Country.html
 
Required for all countries where you have lived for more than 6 months since the age of 16 and any country where you have been arrested, even if you were not a resident there.  U.S. police certificates are not required.  Police certificates from certain countries are unavailable or are obtained directly by your Embassy (rarely does your embassy execute this step).  Fingerprints are required for certain countries.
 
Generally available, reliable. Persons should apply for a certificate of no criminal record at the local Public Security Bureau (PSB) (or certain types of employers such as state owned enterprises), then make application to the notary office for a certificate based on the PSB document. Persons without a criminal record will be able to obtain a certificate to that effect. Certificates for individuals with one or more criminal convictions will list all convictions for which records still exist. The certificates purport to reflect all criminal convictions during residence in China. Police records are generally not available for the period prior to 1949. Certificates are available for those in the J-1, Z, and X categories. The GOC does not issue police records for temporary residents of China in L or F visa categories.
Police records also are not available for those who were in China in diplomatic status including those working for international organizations such as the United Nations. Notarial police certificates are based in part upon records from an individual's employer. If an employer refuses to release records, the notarial office is not able to issue a certificate. This is the case for persons sent abroad for education by the Chinese Government who fail to return to China.
According to a 1957 state council ruling that is still in force, the imposition of a re-education through labor (Lao Dong Jiao Yu) term does not result from a criminal conviction. Administrative organs, rather than courts, impose re-education through labor. It is important to distinguish re-education through labor from labor reform (Lao Dong Gai Zao), which is a sentence meted out for criminal offenses.
If you wish to obtain a criminal record clearance from the Chinese authorities, you will need to apply for a Certificate of No Criminal Record 无犯罪记录证明
 
* To apply for a certificate while you are resident in China, you should apply to your local Public Security Bureau.
* To obtain a certificate after you have left China you should contact the local PSB. However you can also try service companies that offer services to help foreign residents.
* In Shanghai's district (Including municipality of Shanghai, provinces of Jiangsu, Anhui and Zhejiang), the local Notary Public is responsible for issuing such a certificate.
* In Guangzhou and Shenzhen, the local Notary Public is responsible for issuing such a certificate.
* In Chongqing's district (Including municipality of Chongqing, provinces of Sichuan, Yunan and Guizhou), the nearest police station (to be visited first) and the local Notary Public are both responsible for issuing such a certificate.
* In Beijing, the Shuang Xiong company offers this service for current or former residents of Beijing
 
Their contact details are:
 
No.3 Dongdajie (100m east of Public Security Bureau), Andingmen, Dong Cheng District
Tel: +86 10 6402 7616 / 6402 7596; Fax: +86 10 6402 7596
website: www.shuangxiong.com.cn (not current - 9/7/2011)
Email: shuangxiong516@sina.com

I would think if you left the country every 90 days on the first Visa's you had you never hit the 6 month requirement to need a police certificate. Now on your last visa since you have stayed over 6 months continuous from March 2018, you would need a police certificate for that timeframe. I am not 100% on this, but I'm pretty sure it's 6 months continuous residency before you are required to obtain a police clearance certificate for that country.

Packet 3 is the "Instruction Package" For standard processing posts (not many of them anymore), this is what the embassy sends out when it receives the petition from NVC. You return package 3 with DS-230 Part II to request your interview be scheduled.
Packet 4 is the "Appointment Package" This is the package that has the interview appointment and the final checklist of what to bring to the interview.
With NVC appointment processing, Packet 3 & 4 are obsolete, as you are really completing packet 3 when you return DS-230 Part I & II to NVC with the original civil documents, and NVC is really sending you packet 4 when the interview appointment is scheduled by them.

I think you already know your answer, it seems you answered it yourself. It can be very similar to the original one, yes! Just make sure it has a date on it closer to your interview date and the new addressee should be the embassy.

I received the interview checklist in my email and the odd thing is my fiance (beneficiary) didn't receive anything. Anyway, during the initial stage of k1 visa, my lawyer wrote a lengthy letter of intent to marry for both of us and it was very romantic :D. I would like to know whether my fiance needs to carry the same one from both of us with a new signature of us. I did some research and the consulate usually looks for an updated letter. I checked some sample letters online and they are very brief....just 2 lines with the intention of marrying within 90 days. They are not as elaborative as the one my lawyer wrote initially. Can someone guide us?
 
Thanks

All you need to do is write a statement saying that both of you are free to marry, and that you intent to marry your beneficiary within 90 after his/her arrival into the US. There are example here on VJ and on the internet that you can look at. You don't need a long, drawn-out letter, just one that include all the elements. You can either write two letters, one for your fiance(e)(saying they can and intent to marry you within 90 days once they get here) and one for you (saying the same thing). Have your fiance(e) sign and date the letter. You do it as well. 
 
Also, like I did, you could write one letter saying that each of you are going to marry each other...etc, etc.. then both of you sign and date it. It should be no longer than 1/2 page. 
 
Edit: It does not need to be notarized.

Contact USCIS asap and explain the situación so that they can guide you! Dont wait any longer 

I don’t know the answer on that question. I believe it’s best to be honest, and explain in a letter your mistake and send it in with additional evidence. I was asked to send an intent to marry letter too. I only sent in a letter from my fiance. Sorry I can’t be more helpful. Maybe someone with more experience can help you with that question 

Thank you. Those were my thoughts too... if a war begins he won't be able to leave at all. I care about his safety first.