We'll get that sorted out in the next version - if there are no PoW blocks produced until block 6000 (which at this point looks like that will happen) it's a pretty easy fix.  Re-starting PoW after it had stopped seems to make the wallet a wee bit touchy, we can revert to the way it was after we pass block 6000 and it should sync just fine like it used to before the changes were introduced.  We'll keep it the way it is right now so we don't cause unnecessary forking.