It’s just not my day today. Seems the spacing was off by 1mm between the stamps. User Timm from stampcommunity.org picked up on the discrepancy.
So here are the new files:
US Letter PDF: Kiev-Overprints
A4 PDF: Kiev-Overprints – A4
Scribus file you can hack yourself: Kiev Overprints
I am deleting the old post to avoid confusion.