I hear what you're sayin' about her O'ing later in previous cycles Patty. Only problem is that the months that she O'd later, she always had some type of fertile CM at the time. This time, at CD 21 she's marked as dry, kwim?
Personally... I'm sticking with CD 15 and a Stair Step Rise pattern. You don't generally seem to experience Pre-Ov temps as high as what you had this month... and I think those high early cycle temps are what are really making things look wonky.
I'm leaning toward the camp that says Pre-Ov temps can be erratic at times. I think the high temps right after AF seem a bit outside the norm of
your pattern, so I question how much weight to give them when considering where your cover line might be. I see a return to more normal level temps by CD 11. They seem to hold steady until CD 15, where I see a temp jump and a fall back into a stair step rise.
I'm really curious to see how this cycle turns out because this is a really interesting chart!! Not to make you feel like a science experiment or anything! But because there are different possibilities... I'm curious to see how it all actually ends!