Belated thanks for the new thread and title.
JMO, but maybe it's just 10th seat down the row, with the DDoE, Anne/Tim and maybe the Gloucesters as a buffer for the Waleses for the seating, TV close-up shots, and leaving the Abbey. I'd imagine working Royals going back to BP in carriages will all leave first.
Then Haz can't do anything "creative" to get in a shot with William, like changing sides during the walk at PP's funeral or doing a Smeg and barging through the seats.
We might get the odd mugshot here and there of the "slapped arse" face, but he won't be able to complain he's not "front row".