Welcome to Smogon! Take a moment to read the Introduction to Smogon for a run-down on everything Smogon, and make sure you take some time to read the global rules.
If you're +6:30 and i'm -4 that means we're 10.5 hours apart. It's 11:00 AM right now, and we agreed to play at 9 PM my time / 7:30 AM your time. So when I sent the message around an hour ago, it was 10:03 AM, and 11 hours until we played our match. It is now 10 hours until we play.