Zoom free meeting time?

I am using the free service of Zoom with the limitation of 40 minutes timeout and 100 participants. I have turned on the option for participants to join the meeting before host anytime. Suppose, 3 participants joined the meeting at 3:00 pm. I (the host) joined at 3:10 pm. Then when the free meeting would terminate automatically? 3:40 pm or, 3:50 pm .