glennw84

No it doesn't necessarily. I got an RFIE for my I485. The I485 was put on hold (said so in the status update) and once the response was received they started working on it again. Meanwhile my other cases were not put on hold or reset. I called the hotline and they confirmed it.
 
Cases are only reset when a real vital piece is missing. Like the service fee, proof of identity, blank pages, missing I-94, etc. My RFIE was for birth certificate of joint sponsor

AP allows you to travel to and reenter the US.   Your overstay does not matter with AP.  You will not be using ESTA to travel to the US.  You will use AP to travel to the US.

You can call them to check, but they probably can't do anything. If your case is ready to be scheduled for interview it means that your case is transferred to the local field office and it depends on how fast they work there. Check the timelines on USCIS website and it can give you an estimate.
 

I just checked the USCIS website and there is an update saying my card is mailed to me. I didn't get an email or text notification of this yet.
It states that it should be here by February 5th. Let's hope it doesn;t take that long!!!

Yes you would lose all the money and time you have invested in the immigration process. Should you leave now and return to the US later you would need to apply for a CR1 visa, which can take a long time, even if you have had a K1 visa before.
 
Your EAD and AP should be approved around 90 days, the green card can be issued anywhere from 3 months to one year so if it were me I would just wait and then decide. 
 
Why can't you work as a doctor in the States? I am a physical therapist and I admit it was a pain in the butt to get my education credentialled to get my professional license, it took 18 months! Also I need to go through a whole process if I want to get licensed in another state, but it is not impossible. I know there is a big need for doctors anywhere so finding a job shouldn't be a problem if you get your license here. I think that for doctors and pharmacists it is not that hard to get a license as for other health professions, but that's hearsay.
 
I don't have a SSN yet, but I have insurance through my spouse's insurance. You can always get a private insurance or an international insurance (e.g. Alliance) for which you definitely don't need a SSN.
 
After Trump got elected my first response was to get back to Europe as well, but I didn't want all the trouble to have been for nothing. Building a new life in a new country is not easy,but it will be worth it in the end. 
 

You fill out another 864, but this time check the box that says joint sponsor

Apparently that's not the case anymore. I had a request for initial evidence for I485 (birth certificate for joint sponsor was missing). I called USCIS to ask if the timeline for my I485 and other cases would be reset or delayed. She said that it would only affect my I485, it would be put on hold until they received the evidence. The I485 is ironically the only case so far for which I have received a status update.

So even if the marriage would take place a few days after my VWP expires and the I130/I485 are filed later it wouldn't impose bigger problems? The answers I get from lawyers are always freaking me out. Everyone of them says it has to be filed within the 90 days. I don't know if they say that to get you worried so you'd hire them or if it is actually true.