Can not Keyframe Patch tool

Hi,
I have an other question:
I want to Keyframe the Patch tool, (in a panning shot want to disable it before it goes into a building.)
In the keyframe editor No 2 (I use 2nd node) when I open the corrector menu, I can enable all functions (the diamond besides the lock) -only the Patch Replacer does not turn red. I found out, that I am able to enable the keyframes at the first frame where there is a diamond.
But that is what happen: At start, the Patch Replacer is enabled. This should be untill 11sec. Then I want the Patch Replacer off. When I set a Keyframe at that position, nothing happens. Or better-there is no on off switching at all. It is either on all the way or off from start to the end.

Does this keyframing not work on the Patch Replacer?
Or am I overseeing something?

Thank you

Have you tried keyframing the Global Blend?

No, I did not try that. Yes, it works well too. But during my experimenting, I noticed that I can keyframe Replacement Detail (set to 0) and Blur Sharp Edges (set to 1) removes all Patching.
But I think, using Global Blend is far easier to use.
It looks like, it is impossible to switch off Patch Replacement with Keyframes but it is even easier to work with Global Blend.
Thank you very much for your help!