This police station has very complex opening hours! They are described as:
" Every Tuesday 12:00-14:00
Every Thursday 12:00-14:00
Every Second Sunday 11:00-14:00
Two evenings a week between 17:00-19:00, advertised locally in advance".
I have it tagged as opening_hours = Tu 12:00-14:00; Th 12:00-14:00; Su 11:00-14:00 “every second Sunday”; “Open 17:00-19:00 2 evenings per week (advertised locally)”
I think that value will fit your opening_hours tag: opening_hours=Tu,Th 12:00-14:00; Su[2] 11:00-14:00; 17:00-19:00 "2 evenings per week (advertised locally)"
Does “Every Second Sunday” mean “once per month, on the second Sunday of that month” (which is the Su[2] suggested by others), or “alternating every week, so one Sunday it’s open and the next it isn’t, repeating but not dependent on the month”? The latter can kind of be done as week 1-53/2 Su 11:00-14:00 or week 2-52/2 Su 11:00-14:00, but might need to be changed from one to the other depending on the year and when it’s supposed to “start” each year.
Having engaged my brain now, I’ll have another go.
I think you are correct. If something is only open on the second Sunday of the month, then that is usually what people will say. “Every” suggests that it is the alternate Sundays, the problem is you need to know when that started.