OldUser

UP TO 6 months per entry, but that is not a guarantee and also doesn’t mean that somebody can stay for 6 months, leave and come back for another 6 months. 

There's no separate form and the fee is included in the total since April 1st.

I see, I knew DMV / BMV. Now I know of DPS 😃

SSA - YES.
What's DPS?
 
Could have removed it when you got GC. But now can do it in one visit: update status to US citizen and file SS-5 for new SS card without restriction. After oath of course.

If you are filing, you have to declare your entire income, regardless where from - that you made in the tax year. It might be low enough to qualify for no filing but you are filing, where it was made doesn't matter in terms of having to report it but it does matter from perspective of paying tax on it.
 
https://www.irs.gov/individuals/international-taxpayers/foreign-earned-income-exclusion
 
https://www.irs.gov/forms-pubs/about-publication-519
 
These two pages should be of your and your husband's interest. You have to file since you do have GC, therefore substantial presence test does not apply. 
 
The question is still in N-400, you will just simply respond to it "No" (as you have never not filed a tax return - provided it is true going forward as well).

Courier bag arrived at work on Monday morning (yesterday), had passport and papers in there. I gave him the bad news, he was pretty bummed, but he was happy for me.
 

Did you have income in 2023 elsewhere ? If yes, you have to declare it (and you may fall under foreign income tax exclusion and not pay any tax to IRS). This will also make things easier (if you do file tax return) when you file N-400 and have to answer the question about whether you have ever not filed a tax return...

- yes you'll get the 48 month extension letter once your i751 form has been checked over to see if it's been filled in correctly.
 
- once you have a 10 green card you are a permanent resident, so even if your green card expires your permanent resident status remains ie it's not tied to the 10 year expiration date on the card. - I think that's what you might have read about regarding the green card expiry is not a problem. Just to be clear for a conditional 2 year card the date on the card very much does matter and the i751 application must be sent in. 

There's always a risk travelling on AP.
Ideally, one should not travel unless it's an emergency. I think somebody on VJ posted experience being lectured by CBP saying it should only be used for emergency when they're trying to enter the US. For the travel dates and destinations, one can always put "To be determined"

That and the CBP carrier guide.  Sometimes you have to educate the airline clerks, and others.  This is somewhat off topic, but often prior to COVID my wife and I would route through Beijing when traveling to Central Russia, I don't know how many people I had to educate that neither her nor I needed a China visa since China allowed 24 hr visa free transit.
 
https://www.cbp.gov/sites/default/files/assets/documents/2023-Nov/Carrier Information Guide ENGLISH.pdf

Yes, especially if you lose the card. When I had it I wasn't traveling for this reason alone. (I wasn't familiar with the land border option then.)

Can take 6-8 months, which is a well known drawback of the K-1.
 
You cannot work remotely prior to having an EAD or GC.

Just on a side note, has there been any consideration of getting married and filing for a spousal visa, rather than a fiancé visa?  There are pros and cons to each, but a big pro these days is the spousal visa is significantly less expensive and would allow your partner to enter the US without restrictions on work and travel.  

The biggest challenge with the AP is dealing with airlines that are unfamiliar with the AP as proper documentation to enter the U.S. legally.

Yes, she can file I-131 for any travel including leisure.
 
You have to remember it’s one form but there are many visa categories that have to file, for other ones it’s strict. When I filled this out I put TBD on all those travel dates. 

And this should be my husband and I. It's a joint tax filing so you are equally filing with him whether your income is $0 or not. There's a reason he's filing MFJ because he's getting more money back in returns using his spouse (you). If he's filing as MFJ this year then you don't need to do anything extra, it's a joint filing. And the joint filing your income will be $0 if you earned no income last year. 
If you are guys are fling MFS this year, then you as an individual are not required to file if earned no income last year. Or you can still file with $0 income MFS, it's up to you.

You guys won't continue filing as MFJ? 
2025 tax retun filing is for income made in 2024, 2024 filing is for income made in 2023, and so forth. So since you started working this year (2024), your US income will included in 2025 tax filing.
 

After the ceremony, your spouse be given the necessary certificate required to apply for the passport. 
 
If you need your passport fast, then read this…
 
https://travel.state.gov/content/travel/en/passports/get-fast.html. And this
 
https://travel.state.gov/content/travel/en/passports/get-fast/passport-agencies.html

Yes if eligible

Yes people file mandamus on I-751 all the time. And if N-400 is pending while I-751 is pending - both get included in the lawsuit.
 

What @NorthByNorthwest said…Spain will allow dual citizenship. On obtaining a second nationality, Spanish law requires that you declare your intent of retaining Spanish nationality and you only have a short window in which to do so.
 
this is the internet, you will get differing opinions. Your best bet is to talk with a Spanish immigration lawyer in your former country to get the most up to date laws.  

Last I read about it Spain does not permit dual citizenship in general, but  if you are born in Spain you can keep your Spanish citizenship after acquiring US citizenship _if_ you declare your intent to do so within three years of acquiring it.

Yes, you need to be careful when going through the K1 process.  If you and your fiancé refer to each other as husband and wife, particularly during the interview, or with evidence you submit, it can lead a CO to rejecting the application.
 
Good Luck!

You seem to expect:
1) USCIS work fast and provide consistent experience
2) People on USCIS help line to tell you truth
 
Neither is true...
 
4-6 weeks for checks to get cleared and receive notice in the mail is the norm. I wouldn't worry about checks clearing or receiving notice in the mail until May 5th or so.

Agreed, @Juan Hernandez are you married? K-1 is for fiance not wife