Well the trick is to schedule the meeting at hh:mm, but start it at hh: mm+5 and then just make this a policy organization-wide.

In academia (mostly European) this has been a concept for centuries to allow changes of classes to happen: https://en.wikipedia.org/wiki/Academic_quarter_%28class_timi...

So you can have a c.t. event (cum tempore = with time) or a s.t. event (sine tempore = without time).