Delete requests in PSA only between 1 and 10 days automatically

Hi experts,

in our company we face the following problem:

- every month data is loaded into PSA on the 1st and the 8th working-day. --> 2 or more requests with almost same data

- we would like to keep "old" data in PSA

- we would like to use a process chain for doing this.

I found a possibility of how to delete requests "older than x days" - but that´s too much of deletion!

Only requests of the last, say 10 days should be deleted.

Have you got an idea how tho solve this?

Thx a lot and all the best,

Thomas