gandalf backed out a few landings to l10n-central for aurora for your locale, because those were strings that landed in en-US post the aurora cut for en-US. Now, on the next time you want to merge your work from central to aurora (around May 17), those backouts would just stick and remove the strings from your work again. The way to make hg likely do the right thing, or at least throw a merge conflict at you, is to land the "backout" changesets from aurora on l10n-central, back them out, and potentially merge. Double negation style, yeah, somewhat hard to wrap your head around. I can do that for you, but I want to make sure that you're good with it, and that we find the right time window so that your hg work doesn't clash. Sorry for the trouble, I'll do my best to make the next iteration suck less.