If you use BlockFace in any way, to compensate the directionals being incorrect, you can still have backwards compatibility if you add in the handling in your plugin:
boolean legacyBlockFace = BlockFace.NORTH().getModX() == -1; (and then handle it accordingly)
If you didn't special case your directions to fix what's being fixed here... Hurray! Your plugin should now work.
By: feildmaster <admin@feildmaster.com>
Bukkit/Spigot