I'll call whitetails from day one right through to the end of the season. It's just knowing how to call and what to call when. I refer to it as taking the deer's temperature. (we use that in turkey talk too).
Rattling, well I'll start in maybe 2 weeks, 3 hours, 10 minutes.
I'm not a fan of rattling, tickling except for a last resort when a deer won't come to my calls.