I don't think they go fully dormant in their native climate, ie they don't stop growing completely. They start producing much smaller "winter traps", and produce them at a much slower rate than in the summer. The hibernaculum is for Drosera (sundews), not flytraps. I think you should expect them to be quite dormant for about 3 months, roughly December through February. I would guess that they would be starting to slow down by now.
-Don

They will begin to really go dormant in November as the seasonal day length shortens. Photoperiod is the main cue for plant readiness for dormancy but temperature is the final cue for dormancy after photoperiod. A plant that has not received enough photoperiod cues before constant freezing weather would probably die. Short frosts are fine for now and the plants will grow slowly through those.

Dormancy isn't an event; it is a process that actually begins right after the summer solstice. It's just more noticeable in the fall->winter. Just leave them be and let nature cue the plants.