This is coming from the Ag Skies 2 modpack, however the person running that github requested that I notify you guys about it in case it was happening outside the pack as well.
The base world here is a void with everything nearby as Ocean or Stony Beach biomes, and I'm testing some bee stuff in creative.

To wit;
http://imgur.com/a/4fQIe
The terrestrial reformer from Witching Gadgets (Thaum) appears to be clogged or something, because it will stop changing the nearby biome halfway through the process, leaving random bits as ocean rather than whatever it's supposed to be changing it to. It's the most obvious with the jungle area because the vines are different shades depending on the biome, as shown in the second and third pictures.
I've also made a desert area in the same test world, and the reformer there has stopped at this point;
http://imgur.com/B7wfYeD
The color of the grass should be a greenish brown all the way across, but it's been sitting there for twenty minutes or so now, and the F3 biome note stopped changing about five minutes in for every block I checked, and the glowy line from the relays, which is supposed to be green while the machine works, turned white and stayed that way at about the same time.

Reloading the world seems to fix all these issues, however.