I'm not sure there's any "court ruling" of that sort. The only applicable case would be Wightman, which just confirms that revocation must be and “unequivocal a

I'm not sure there's any "court ruling" of that sort. The only applicable case would be Wightman, which just confirms that revocation must be and “unequivocal and unconditional decision” on accordance with a country's “own national constitutional requirements”. You may be thinking of the Advocate General's initial opinion, which accepted that unilateral revocation would be possible only if it did not involve an "abusive practice", under which the idea of revocation followed be immediate re-notification might be considered "abusive". However, no reference to this appears in the final judgement of the CJEU.