Well Martin, I feel your pain on being dragged along a REO closing. I have a client right now in Tampa, FL who is going through the same thing. She was under contract in early Feb and was supposed to close by end of February. Then got bumped to March 8, then March 23, Then now April 8th.
The underwriter with your bank is looking out for your best interest and theirs. And since the extension keeps going on, she needs to make sure nothing in your life has changed, like job, new debt, credit etc. With REO's banks need to satisfy all previous leins on the home like water, sewer, trash, electric, contractor work, taxes, permits, everything. Sometimes there are circumstances where there is difficulty with those leins getting amounts due or insurance claims in process. Your title company would be handling all of that and negotiating with the bank to get them paid at closing.
If you are in a need to move in by a certain date, have your agent draft a early occupancy agreement. This shows the bank you are still interested in buying the property but the delays in closing aren't feesible for your current living situation, like your rent is up within 2 weeks and you already told your landlord. If anything, ask your agent to pry information out of the title company of why there are so many delays and have them be your advocate on getting this closed in a timely manner.