Could you try your antminers now? I implemented ntime rolling support for the time job is alive - in seconds.
So far the rejects are looking MUCH better ... still a high number of discards, bit I'm having trouble trying to figure out how minter12345 was able to get that log output ... :-/
BTW ... with an AntMiner S1 being 180-200GH/s, what would you recommend as the diff? I've been using the default of 512 ...