Somehow I doubt UA will "go under". The government wasn't about to let that happen with TWA - in fact, honoring Aviators miles and existing tickets were key requirements for AA to get a smooth approval for the buyout. If you've got travel planned in the near-term, I'd be looking for a backup plan. But I wouldn't flush my MP account at a big loss because of the possible strike.

On the other hand, if you just hate UA and want your miles out of MP because the thought of another trip with them is unbearable, I understand. Go the DC route or, if you have enough miles, book at cruise4miles.com.