You may want to take careful note of the issue ~laGrenouille raises about others' contributions, though. Say a patch/pull-request is freely offered to your AGP

You may want to take careful note of the issue ~laGrenouille raises about others' contributions, though. Say a patch/pull-request is freely offered to your AGPL project. I believe it's well-understood that such a submission includes implicit permission for distribution under that same open-source license. But you will also be licensing that same contributed code under another custom commercial license. Contributors should understand that – you've made it clear in surrounding docs – but whether you can legally assume their re-licensing permission, without an explicit copyright-assignment, is a bit murkier of an issue.