How to synchronize ECC master data with GTS master data?

Hi

We've been using GTS in Prod for 2 years already and just last month I realized that we are not getting any update for BPs that got deleted on ECC.

Suffice to say that there are more than 100,000 customers/vendors that got deleted (both hard and soft deletion) in ECC and are still being screened in GTS (what a wast of time and performance).

1 - Do you know what is the best way to sync this data (make sure whatever was deleted on ECC is also deleted/archived on GTS)?

2 - How can a deletion (hard or soft) in ECC be automatically replicated to GTS?

Thank you so much.

Debora