Started a question at Stackexchange:

I modify open source software that is under ‚GPLv2 or later‘. I will upgrade to GPLv3 or later – that‘s of cause no problem at all. Not looking for advice in this case, but is it possible to upgrade to AGPLv3, too? The info provided at gnu.org/licenses/ are not clear for me. In short: GPLv2 or later -> AGPLv3, possible, yes or no?