Hi. Now is a good time to start thinking about pruning, and you are basically correct about the insect issue, though it is a question of when an oak is dormant rather than whether or not there has been a hard freeze. Timing is less of an issue for hickories because the specific issue you want to avoid is oak wilt disease. This article from last year’s Ohio State University’s Buckeye Yard and Garden Online Newsletter emphasizes the importance of pruning oaks in the dormant season and includes some more information about oak wilt that you might find useful, including this link to Ohio State’s fact sheet on it. The fact sheet indicates that oaks should be pruned after October 1st, and the BYGL article says that they should be pruned after October 15th. In general, you should be safe at this time of year (early November), but it has also been an usually warm year, so I would suggest waiting a bit longer to be on the safe side. There is no downside to waiting a bit longer. I think many certified arborists don’t prune oaks until December to minimize risks as much as possible.