I don't believe so (although this is probably fact-specific about what "accidentally" means), at least with regards to retracting the licence. The GPL is an irr

I don't believe so (although this is probably fact-specific about what "accidentally" means), at least with regards to retracting the licence. The GPL is an irrevocable licence. They could choose not to continue to distribute the code though (but good luck clawing back the GPL licenced copies).