I'm 37 and I've never managed more than one pop in an hour, even when jerking myself off for the second one, and believe me I've tried. Even having 3 gorgeous ladies tend to me for the last 15 minutes of a Lady Marmalade Party didn't get me there, and nor did several different Thai duos. I've now fully conceded, as frustrating as it is, that I'm just not meant to enjoy the privilege of more than one pop in a single punt.
I only started punting last year, and before that I never felt the need to try for a second pop in such a short space of time with civies. I can but wonder as to exactly what age I would've been able to get ore than one shot off, but that's something I'll never know. Now, knowing that I need at least 2 or 3 hours before I can pop again, I never bother with booking for anything longer than an hour.