Ripple deleting markers only working at end of sequence

Hey there,

I'm splitting up a 10 hour video with lots of markers into 4 parts.

My workflow to far:

1. duplicate sequence 3 times to have 4 of the same
2. select desired range with in/out 
3. make necessary cuts at the beginning/end
4. track select forward/backward
5. ripple delete
6. export markers
7. export footage

This works for the first sequence only, all markers, although ripple deleted - plus Ripple sequence markers checked - stay in the csv, though the times are correct in the 1st sequence (I can just delete the rest in the CSV file). Beginning with the 2nd set of markers, the times are completely off, and the deleted markers before and after the remainder of the sequence are also present.

I'm guessing I missed something vital!
How can I get rid of those markers for good?

Edit: I figured that all markers from the ripple deleted parts pile up on top of each other at the beginning/end of where they got deleted from. I can mark them in the markers panel and batch delete. I'm just wondering if there's no more practical solution.