Hi Ali,
Yes, You can switch of SID generation when dso have data. there is no issue.
it just stop sid generation next data load onwards.
Switching off doesn't impact on your load to cube or open hub.
Once data was active at dso, a per the process dso data will move to target.
You can try to set sid offs at table level for your data source.
Table - RSODSO, Field is BEXFL - need to be as blank.
Or You can do at dso level. After the changes activate dso.
First lets try at dev system and check it.
Later you can move you Changed DSO structure to prod.
Thanks