Calendar federation

Is there a dependency on a 8.5 server to have federated calendars?

I have a 8.5 client and an 8.5 mail template running on a R7.0.3 server and I can overlay a calendar. Should I expect errors in the future or is calendar federation strictly dependent on a 8.5 client and 8.5 mail template.

Thanks

Subject: Calendar federation does NOT require an 8.5 server…

any issues would be caused by replicating the 8.5 mail template to a 7.0.3 server that did not understand some of the things that the newer template was asking of it. If you do not replicate design changes back to the server, you should be all set.