I also was under the impression that all translations based on the POT from PR2 were supposed to be meant for the RC. But, as I am defenitely no specialist, my knowledgelevel is far to low, I could be wrong.
I am mentioning for which branch the pot file is, you just have to read the text I wrote. So I provide pot for both branch, it is up to you to know then for which branch you want to work with the pot file I propose.
I even generate again all the .po files for both develop and rc and then propose 2 distinct pull request, but they are not committed and in between you publish your nl.po file which gives conflicts so I close on of the PR.