We had a oil/poly satin finish done over a some new and some refinished oak flooring this past winter. The results were not very good. Dimpled and bubbled all over the place. The contractor claims that this was caused by a power outage overnight that allowed the temperature to drop in the house while the finish cured. The power outage occurred about 7-8 hrs after the finish was laid down.

What do you guys think? It was my understanding that bubbling was caused by improper mixing and/or over working the poly as it is laid down. Additionally, there were other sections of the floor that were done on other days that didn't experience any power outage/temperature issues that had the same problems - bubbles & dimples.

I should say that there is some disagreement of how cold it got in the house overnight. Contractor says "freezing". I visited the house in the AM and there is no way the temp was below 50 degrees. Power was out no longer than about 8 hrs. There were no houses in the area or town where the pipes froze, so it is unlikely that temp went below freezing.

Thanks in advance for your thoughts.

That's a kinda tough call, but given the time frames we are looking at, i.e., power went down 7-8 hours after finish was applied, power off only over-night; and the fact that the same problem is evident in other areas that weren't subjected to the same conditions; I would say that that is not the cause of the issue.
Many factors can cause what you are looking at, including the two you mention. Too much working of the finish, or sunlight hitting the finish before it sets up are two common causes. Also cross-coat contamination or some other external influence can create problems as well. Too short a period between coats can also cause these things.

Buff, clean, and re-coat is the best solution.