We did this cruise. However we did not do the high tea. You are right. It is the same day as the feluca ride. The people who chose the high tea were let off at the hotel from the feluca ride. The rest of us continued back to the river boat.
Our feeling was that the tea was crammed into a very long day. We were ready to head back. The people we spoke to who did the tea confirmed it was more of a rush job. They were disappointed. Just our opinion. Maybe someone else will chime in.