> I do not understand the difference between "redistributing a file > under a GPLv3-or-later license", and distributing it under a license > that is GPLv3-or-later".
I'm not sure what the two things you list are, but the two that we're talking about are: (1) Distributing a GPLv2-or-later file as part of a GPV3-only or GPLV3-or-later package. Everybody agrees that you can do that. But when you do, the recipient of the file can choose to further redistribute it under GPLv2 if they want. (2) Changing the text at the front of the file to say "GPLv3-or-later" when it currently says "GPLv2-or-later". FSF *policy* (not the GPL) requires that all files have "GPLv3-or-later" license. The question is what permission you need to change a file that has a "GPLv2-or-later" license into the required one.
