You were living right. Or maybe karma was evening things out for you.
OP, download the Mousewait app and you can watch for yourself. It is currently reported at 12 minutes, but that is not typical. Perhaps they have cut the line for the day. I don't recall, it might close at 5 local time.
Most days when I check the app it's between 90 and 135 minutes.
And I do think that on odd occasion it's just one sister or the other, although we were lucky enough to meet both when we were there in December.