Hi @Sylvain!
I just wondered if this has been discussed internally, since I am eagerly awaiting this feature too.
Throughout the workweek, I often find myself moving workouts to the weekend, due to lack of time in the workweek. However, sometimes I’m not able to finish a workout on one of the weekend days, meaning I would want to have some buffer at the beginning of the next workweek. Thus, with this feature implemented, I would change the first day of the “week” to Saturday.
I also found a different post requesting this feature, see that one below: