I’m not clear on the use case for this. It seems like with a resub chat message notification and subscribe/unsubscribe events you should have the data you need.
An error occurred while saving the commentone_suit_samus commented
Agreed, EventSub is feeling like a second class system without this information provided. I don't see a need for a separate subscription item for resubs vs. first time subs; I think the existing item should have resubs and tenure information included.