Kev, no one direct answer to this. Assuming that you're asking if you can simply re-harden the steel. Technically, no......you "should" do an anneal prior to re-hardening A2. But....there are testimonies from A2 gurus that have re-hardened A2 without problems. From what I understand, the main concern is going to be massive grain growth. But, there is a smidge of Vanadium in A2 which helps, and as long as the Vanadium carbides haven't been dissolved (very high heats), then you can probably get by. I think, and you may want to contact guys like Kevin Cashen, Devin Thomas, Robert C (mete), when re-hardening A2 from already hardened (martensite) state, shorten the soak time 2nd go around. If you did 30 minutes first, do 15 on the 2nd attempt. Good luck.