covid vaccination dates for doctors

[chrisbonn]

due to various requests from doctors: Is there a possibility to set the time for an appointment smaller than 10 minutes? Background: vaccination appointments for the Covid vaccination are to be assigned and as many vaccination appointments as possible must be assigned in short time intervals, specifically every three minutes.

Another question: Is it possible to automatically set a follow-up appointment exactly six weeks later at the same time?

If it were possible to implement this, what would an extension cost and how quickly could this be realized?

[Bromptonaut]

I tried this workaround:
create one single slot using the appointment-app. Then access the respective calendar containing that single appointment with another app, modify the duration of the entry created before (to e.g. 5 minutes) and then copy it as often as necessary. I used Gnome Evolution to do that, since the nextcloud web-interface for the calendar is somewhat tedious to use. Anything like Thunderbird should work as well.
After editing the calendar, re-open the appointment-app (or just re-load the web page) and you will find all slots as defined before externally. Unfortunately, the e-mail validation does not work with slots shorter than 10 minutes (I have no idea why). The appointment is written to the calendar as tentative, but the confirmation mail is not sent to the person requesting the appointment.

What finally worked: create the appointments with 10 minutes slot duration. After that move the slots so that they overlap by 5 minutes. That way, the calendar looks somewhat messed-up due to the overlap, but it works.