Actually, in this thread Ben (Pooldoc) advises adjusting the pH to 7.8 so the ammonia products formed by the bacterial degreadation of the CYA will form monochloromines and hitting it with chlorine until the chlorine levels hold.
http://www.poolforum.com/pf2/showthread.php?t=1001

Might be applicable here.
Once the chlorine is holding would seem to be the time to worry about Alk and pH.