"Besides that, closing a drill-site is not like everyone dropping his work on the count of three and literally walking away immediately, so I guess even with a done fracjob, fluid recovery, flowtesting and all the completion work, they would still be working on site even if they had already decided to abandon the well"

FYI

Funny enough, when a decision is made to shut in and discontinue operations, that is exactly what happens.

Step 1: Get word from company man that they want to shut in and rig out.

Step 2: Shut in and rig out

Trust me, They do not want to pay $100,000+ per day for crews to stand around and do nothing. I would also doubt that they would abandon the well as there may be other opportunities in the well bore.