When to give boss notice I am moving/leaving (long, sorry)

Backstory: DH is in training for a federal agency and not home right now. We received his new city assignment 2 weeks ago. (Generally moving east coast to midwest-- so it is a considerable distance.) He will not be finished with his training until the end of September.

I would like to work as long as I can before we move. However, if our condo sells before the end of September, my plan is to move to the new state (with my parents temporarily) when it sells versus finding a short term apartment here.

While I am not a teacher, I am employed through a local school district. My supervisor will be very upset that I am leaving at the beginning of the school year. I want to give her adequate notice, but she is the type to unofficially make my job very difficult for me (due to not being happy about me leaving.) I also would like to give my patients adequate time to prepare to the new adjustment of a new therapist.

If you were me, when would you tell her you are moving? I was thinking about 30 days prior to the move. So if we don't sell before moving, I would tell her at the end of August. If we do sell, I could tell her about a month before closing. Thoughts? TIA.