30 hour clock

If I go into my scheduled meeting in advance of the actual date, just to test it out etc. -- does that start the 30-hour clock ticking? After I finished my test, I clicked "Leave meeting" (as opposed to "End the meeting"). We're more than 30 hours out from my scheduled meeting, so I don't want that clock ticking and the meeting will have expired before we even get to that date. Thanks!