Is there a 'must complete by' date with the FCC? After DOJ approval I would be considering merging without the FCC and noting a "Failure to Act" as reason to bypass them.
The FCC is destroying these 2 companys without any feedback, ETA's or communication to tell these boys what to expect. The dates they did give them have all blown past.
Their "failure to respond" is criminal.
So just do it! Then when they call to stop them say "wow, did we wake you?" and then consider any rules they may want to impose.
But F'em if they aren't going to act at all. You cannot do business with a mystery-box. They either need to be clear or get out of the way. It has already been determined that this is not anti-competitive.