I would say the chances are between slim and none; had that been in the cards, they would have done that already.
For them to do that
now, they would have to establish a new server farm -- and you can bet that by 0800 the next working day after the shutdown the CoH servers were already being wiped and repurposed, whether by NCSoft or by their hosting company -- with all of the other support servers, along with the Net connections to feed them, and then load the last backups for each game server, the authentication server, the store (you think they'd even
think about bringing it back if it was going to be
just a money sink?), and then contact all the people who had CoH accounts, particularly the subscribers, and
hope that enough of them came back to be able to at least break even on operating costs. And they got enough vitriol from the playerbase during the sunset period to make them believe that they would only get a small fraction of the playerbase back -- certainly not enough to pay for the upkeep, much less make a profit.
Any chance of the game going into maintenance mode died irrecoverably at midnight on November 30, 2012.