Actually, we have the same problem here. For us, we don't want face-to-face to adjust the time. So if the trainer sets the time for 1pm then we want it to show up 1pm. The only way that I managed to do this is I updated everyone's profile and put the "servers" timezone. Thank you csv's!
What I need to do now is hide the timezone field in the profile so no one edit theirs.
We really like face-to-face though!