Broken bit changes

I’m a new CNC
I have 2 Questions
(1) do I need to use the touch plate again to reset the zed, to do a bit change after the ruff in from a 1/4" bit to the 1/8"?

(2) How to change a broken bit in the middle of a carving project and then resume the the project?

As for #1, when ever you change a bit in the middle of a job, you always reset the zed. You do not need to reset the “X”, or the “Y”. Not sure how to start in the middle of the job, but I’m sure someone will shine in on that.

As for #2 take a look at the video by prosper woodworks, i believe he has a pretty good solution.
He carves some stars pauses for bit change and resumes

Andy