It would be helpful if closures on the calendar had the option to indicate that library closure should block holds requests for that library's items, and another option to indicate that library is not a pickup location at that time.

It would also be useful if you could set a hard due date for a library closure.  This would be particularly useful for schools.  So, let's say it is March.  You may have one or more future closures that indicates a hard due date (hard due dates should allow you to specify dates prior to the closure).  Koha rules would look at the closest upcoming event/closer that has a hard due date set, and set the existing rules to that date.  Once that date has past, it would set the next one that is set, if there is one.

If any of these options are set, it would show it in that library's rules or branch (hard due dates in grey on each rule like "before 5/31/2024 (set by calendar)".  If you need to, you can specify a hard due date for any rule, and it would ignore the calendar (maybe until it passed???).  Hold policy could indicate that it is set by a calendar event.  In branches, the pickup location could indicate the upcoming setting and date (or range).