As per https://docs.microsoft.com/en-us/graph/throttling#service-specific-limits, GET Subscription List is limited for an app, across all tenants, to 80 requests per 20 seconds. Our app runs for hund...
This specific limit is for subscription "admin" - creating, listing, deleting, etc. - not a limit on actual notifications. Can you elaborate a bit more on the scope, # of tenants, subscription types, etc. that you'd be creating more than the limit. Any samples or details woudl be helpful.
Barry Gervin