If the MRC denial leaked the approval, FDA was not ready to release to Amarin, once someone realized the approval was basically leaked in that document they halted stock, and then rushed to get paperwork done is a scenario that could apply.
I was just thinking something similar.
The FDA and sponsor are usually more choreographed than what we are seeing here.
This HALT could be for a RegFD filing relative to footnote 54 on page 12 of the FDA's response.