Hey @tulkastri,
You need only ask and be a subscriber. I see that you are so you have now been added. Please check out this thread for info and feedback on the feature which you are welcome to contribute to.
Congrats on the 100/100. Sounds epic. For your specific date question, indeed this planning/programming option has been requested elsewhere and it is on the dev list. For now, indeed, you’ll need to go ‘unscheduled’. Nevertheless, this shouldn’t prevent you from playing around with the new user-time-constraints feature. You can always miss or delete sessions as needed.
Welcome to beta!
Best,
Paul