you need to understand that by policy recruits are allowed exactly two calls: "I'm here" and "I'm a Sailor". In general you'll also get a "I'm still alive" call around week 3-4. Calls are EARNED and ARE LOST as a division and NOT an individual and always at the discretion of the RDCs. You may get more calls.....don't count on it though
to answer your question....anytime/day....have your phone with you all the time
I got a call from my recruit last night (7/14) at around 8:30pm. Spoke for 15 minutes....it was fantastic!