My partner and I use Apple TV to access Zwift and will often do our training sessions sequentially (i’ll ride for an hour and then we will switch users and she will ride for an hour).
It looks like times are carried across between sessions. We’ve noticed this a few times, most recently yesterday. For example, if I ride a world such as Paris and log some lap times and sprint times these times are carried across and displayed in her session as her previous times and 30 day PRs.