Multi-multi-network issue with cross-network email address being used

Hello,

We’re aware that this is an edge case, but want to raise it in case there’s anything that you can do to help:

We run a multi-multi-network (one master network that contains several sub-networks, each with their own sub-sites). We recently added a new sub-network and activated the Offload SES plugin at the sub-network level. A site from a different sub-network has since noticed that some of their emails are being sent from the new sub-network’s notification email address that’s set in Offload SES. The behaviour is inconsistent (not all emails are being sent from the other sub-network’s email address), but still troubling as one sub-network’s settings should be isolated from another’s.

We suspect the root cause is something to do with not having enabled subsite settings on the new sub-network instance and are guessing this might influence how network settings across different sub-networks are traversed when an email is sent. We’ve now enabled subsite settings on the new sub-network to see if this resolves the issue, but if you have any further information that could help us resolve this/avoid it in future, we’d be grateful for your help.

Thanks!