According to Engnath, to heat treat ATS-34, heat to 1975, he doesn't mention any soak times, but I went a half an hour, then air quench. Straighten before it gets below 250, then cryo at -220 for 6-8 hours. Double draw at 950 for two hours per cycle.
I couldn't do the cryo, but the rest of the instructions seem to have worked well for the ATS-34 blades that I've done so far. The cryo can be done at home, though, and I'll be doing it in future.
For annealing air hardening steels, check a thread titled "annealing D2?", there is quite a bit of discussion on the subject there that could likely be applied to your question.
Hope this helps.
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