Habit Goal: X days cycle as an alternative to weekly habits

As a firefighter I spend 24hours at work 1 day out of 4.

It’s way easier for me to plan my habits in a 4 days cycle instead of a weekly schedule.

I would love to be able to set habits in the app that would be flexible (the strict « 4 days interval » is not a good option because I’m sometimes so exhausted after my shift that I need to delay my workout to the next day) but would be anchored to a 4 days cycle.

(Example : go for a run 2 days /4 (and not specifically on day 1 and 3; it could be any of the 4 days).

Thanks a lot 🙏🏼🙏🏼