With help of the users from different time zones. I’ve found restriction regarding planning workouts for tomorrow with free TrainingPeaks account.
Officially you can’t plan workouts for future dates, but practically you can plan workout for tomorrow with free TP account. TP server local time is in UTC-6 time zone. You can plan workout for the next day relative to TP local server time.
E.g your TZ is UTC+2, current local date time 20.05.2024 06:00. TP server local datetime is 19.05.2024 22:00. You can plan workouts for 20.05.2024, you can’t plan workouts for 21.05.2024, you can do it in 2 hours.
E.g your TZ is UTC+12, current local date time 20.05.2024 18:00. TP server local date time is 20.05.2024 00:00. You can plan workouts for 21.05.2024.