How to replicate this issue:
1. enable staging for group A

2. upload a file a.txt in dl portlet of staging env.

3. publish it live

4. edit the file again and publish again

5. repeat steps 4 to ensure at your have several versions in staging and live (for instance 1.0, 1.1 1.2, 1.3)

6. delete history version 1.3 1.2 and 1.1 in staging and publish it again

7 edit the file again and choose a new file b.txt and publish it again

8 go to live and check the file you will noticed the file still is a.txt

expect: After finish steps 7 you should see the file b.txt in live

This issue does not happen on 6.1.x