As of today (May 25) the builds should be fully working again.
Sorry I haven't integrated your EFX changes yet, but they need some work which I haven't been able to get to yet. Could you consider pushing them a bit further? Basically, what is needed is to use the JavaEpilogue directive to GlueGen to insert the call to refresh the AL function pointers at the appropriate place. Based on what you mentioned I think this should basically be
JavaEpilogue alcMakeContextCurrent ALProcAddressLookup.resetALProcAddressTable()
or something similar. Since we don't currently have per-ALCcontext proc address tables (which is a bug in the implementation of JOAL), you could probably put the logic as to whether to actually perform the re-lookup into the resetALProcAddressTable method, if you didn't already have it there.
Could you please implement this? Once it's done there shouldn't need to be any changes to the user's code; the EFX stuff should just magically start working. At that point your patch can be applied unmodified.
Note that I've (accidentally) already checked in changes which make alGetProcAddress visible only in the ALImpl class, so you should be able to get to it from the net.java.games.joal.impl package. See make/joal.cfg.