FrancoBegbie

No employment - paid or unpaid - without employment authorization.
You can use a job offer as a basis to request an expedite.
Good luck.

So instead of it taking 5-6 months to receive the EAD, how long would it take if it gets expedited?

If you have a job offer and the expedite gets approved, you may have the EAD in a month or so, or maybe even sooner.
 
Good Luck!

If you can get a written job offer you can expedite the EAD card. Its a simple process and from beginning to end, took us (and others I have known) about a month from start to finish.

Being a mechanical engineer or anything else makes no difference to the processing time.

You can not work in any capacity.  You will have to wait for your EAD in order to legally work in any capacity.   

You can not work for free for a potential employer.  You can not work for free in a position that is usually paid.  You can not work as a third party consultant.
 
You can volunteer with a charity.  

You have two options: request an expedite of your EAD based on the job offer (employer will need to cooperate with that) or get used to not being able to work in your field and potentially lose out on experience and being “left behind” by the industry for several months. The latter is the exact reason why a K-1 was of no interest to us and why I’m surprised it’s still so popular with people who have worked hard and studied hard to get where they are in their careers only to throw it away to get into the US a few months faster. 
 
If you want to do something productive to fill your time whilst you wait (if the expedited EAD is not successful), you can volunteer in places where people work completely altruistically such as soup kitchens, animal shelters, church groups, etc. That’s all. 
 
I’m not surprised the company did not entertain the idea of you working there for nothing as this would be considered “working off the clock” and can have serious implications for them legally and in terms of insurance, etc. It’s also illegal for anyone to undertake work for which one would ordinarily be paid without any form of work authorization. 

Got the SSN card a while back seems it was just manual verification was required for it. It probably complicated it because I had an SSN card before from a previous visa and lost it. And I applied for a new one, when instead I should of filed for a replacement one.

Okay, good. If it's been sent back, they should have a response. It's just waiting for the SSA to process it.

What is your current status and when does it expire?
Other than pending adjustment of status?

My work had to see the card and made a copy of it. And I'm a USC.

Not sure if I have ever shown anybody the card, they have just wanted the number.

I still had a copy from the I-134 from the K1 Interview, but I just asked my employer to print out a more recently-dated copy for the I-485.

Nothing had really changed in the few months since the K1 interview, and they didn't mind doing it. But I probably didn't need to do it...it was just a pretty easy thing to do. 

Is the EVL current?
Does it state what you are predicted to earn in 2019?
 
Have you used that amount on your I864?
If yes, you should submit an EVL with 6 months current paystubs.
If no, you dont need an EVL or paystubs.
 
Or have you used your tax income in Part 6 Question 7?
If yes, then that's all you need (your 2018 Return Transcript).
 
Bank letter will need to be current for the previous year.
Did you have to use assets to meet the poverty guidelines on your I864?
If not, you dont need a bank letter.
If yes, it needs to be current. 

Moved to AOS from K1 forum as OP is at the AOS stage 

Moved from Progress Reports to Process & Procedures.

The I-129f is not gong to influence the requirements of your local embassy. Produce what they are looking for and you should have no problems.

I have depression and was diagnosed with social anxiety in the past and it was noted on my medical form for the US Embassy. Currently on medication for the depression as well. I had no issues with USCIS but I would imagine it is a case by case basis. I defiantly agree with JFH that you should marry each other because you want to and love each other. Otherwise, you might run the risk of immigration fraud. 

There's not a "hold" really....it sounds like your case has to go through manual verification. You can check the SAVE case status here: https://www.uscis.gov/save/casecheck
 
Did you change your name since entering the US? What's your current status in the US and when does it expire?

Then you should qualify just fine. It's just a matter of time for SAVE to come back on the manual verification.

Okay. If you answer the rest of my questions one by one I can help you figure out if you even need an EVL or bank letter...
Otherwise sincerely, much luck!

Why are you doing the I693?  Did you read the instructions as it relates to a K visa?
 
PS.  An entire forum dedicated to AOS from K, go there and read

I think that should be fine, if you include recent paystubes that indicate you are still employed there. 

Not at all. When the I-131 is approved, you can travel for any reasons or no reason whatsoever. 

You file the i-131 as part of the AOS package.  You do not need a reason to travel.   The I-131 is utilized for many purposes in immigration, such as leaving the country for more than a year.   It is not filed with the I-129F petition.