Can I brake the "transform constraint" relation later in seq timeline?

See, I try to make Natasha to drop a book from her hands:

Is there some tools to brake the “transform constraint” relation in specific time at seq timeline? This way I can use the same book and let if fall down. I can make the falling manually by keyframes for now. Even better if I can use dynamics!

Otherwise I need to somehow hide this book ( animating the opacity maybe? ), have a duplicate book with exact placement and continue from there with manual animating…

I tried to make collider “cage” around the book, and transform constrainted that to natasha hand. It was jittering, jumping and bouncing way too much :) So this needs to be done in a simple way!

I found the visibility key from curve editor!

I made it manually!