Ah ok, thanks for the clarification.
You could maybe help yourself with a trick.
Create a new Property called “First day of the year” or something like this as a Date Property.
On all registration forms, add this new property as a hidden field and set the default value to January 1st of the given year.
This field then will store a reference value like “2024-01-01”
Add a calculated property also, that calculates the calendar weeks with the following formula:
round_up(time_between([properties.createdate], [properties.first_day_of_the_year])/86400000/7,0)+1
This will calculate the calendar week by getting the difference between your set hidden field of first day of the year and the create date of the contact.
You can then easily create lists by checking for calendar weeks. So in one list, you stick all from week 1, 5 81+4), 9 (1+4+4) and so on, in the second list you stick all from week 2, 6 (2+4), 10 (2 +4 +4), and so on.
You will then have separate starting lists based on the calendar week of a given year and can automate.
Only caveat: you have to update the default value hidden fields in each form to the new year on new years eve.