Need some assistance in PRs, PRv design

Hi there,

I have a question to the practicers:
Have you ever done updating data of the one stage DE, based on the data of other stages DE?
What I need:
I have repeatable stages. And I need to update DE - HIV status of the latest event of the stage A with the data in the latest event of the data entered on the Stage B.

Stage B can be added more often, and I need to take this entered data and update current HIV status on stage A.

If you have done such thing or have done in different way please share your experience with us.

Thank you.
Regards, Ulanbek