"Write Project Tempo to Audio File" and "Remove Tempo Information" question

[Bp300]

Hi hope the day is going well:)

I recorded some guitar in a project, turned on flex, used the quantize function and Q-Strength (using Region Inspector), then sliced the audio at the starts and ends of the regions to clean it up a bit. A couple days later, I decided to increase the Project Tempo a bit.

However, now when I drag the start of a region I've sliced (Left Corner), the flex markers move around a bit, and the end (Right Corner) actually stretches a bit further to the right, (even though I'm dragging the Left Corner). Correct me if I'm wrong but I'm guessing it has something to do with Tempo settings/information.

Anyway I'm trying to use the "Write Project Tempo to Audio File" and "Remove Tempo Information" but a little unsure of which to use. (There's also "Apply Project Tempo to Region and Downbeat" which seems interesting). I've made a dud project to experiment with these options since it's saying that these actions can't be undone, but still can't seem to figure out the appropriate one to use in which situation, I get the feeling they can do the same thing, but have different approaches to how they work. I've tried reading the Logic Pro User Guide but don't seem to understand. Does anyone understand this part of Logic well enough to explain these functions simply? And which one should be used in this particular situation?

Edited March 7 by Bp300
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