What is happening with my bbt?

[Nottherealslimshady]

Initially app said ovulation was CD17, I stopped testing after bbt confirmed ovulation even though LH readings were still coming out as high. This, morning app changed my ovulation day to CD21 because of a second temp rise. And moved AF back 4 days. Putting me at a 35 day cycle from my 26-28 norm. I had a 6w miscarriage from my last cycle so was expecting cycle to be a little longer anyway.
So confused and really worn down by it all, I just want it to be easy 😔

Hm I'm not convinced - I'd still say it's CD17. Pop your temps (and OPKs) in FF as that's a lot more reliable usually!

Fertility friend says ovulation CD17, how strange, I really like this app too but if it's not accurate :/

Well the rule is that you have ovulated if you've had a temp shift of at least three consecutive temps higher than the previous 6. Your temp shift is clear at CD18 so I don't know what on earth femometer is up to.