Confusing chart, OPK vs BBT - can anyone help?

[AsSurprisedAsYouAre]

I am relatively new to charting my BBT, this is only my second month adding it to my ttc toolkit, been using OPKs and always considered a positive OPK to indicate ovulation would occur approx 24 hrs later (well, 12-48hrs) but my chart this month has a really clear temperature dip the day before my positive OPK! I got a positive OPK about 4pm on CD 12 and it remained strong until the following morning before fading to nothing before bed CD13. According to Fertility Friend I'm 9DPO today.. but I'm skeptical. Would anyone else agree with this? Any help appreciated - I'm worried I've been mis-timing things for months

I had this too this month. First time ever. I got my dip 2 days before i got a positive opk. I’ve regular cycles, and defo ovulated last month as I got my progesterone checked and it’s looking like I ovulated this month going by bbts. Have mild pco and wondered was it related to it but can’t find anything online to explain it. 🤔

The same thing has happened to me. According to bbt I ovulated Friday but based on opks I would of ovulated Saturday. My bbt is all over the place as I find it hard to take temp same time every morning but there's a clear dip and rise. Sorry I can't be any help. Let me know what you decide regarding what DPO you are

Thanks for the replies! Really nice knowing it isn't just me. I usually have a very regular luteal phase, or at least I thought I did! So I guess I'll wait for AF and calculate back from then. I know it takes a while fro LH to get to the urine, but not peaking until after ovulation, rather than 24hrs before seemed like a stretch! I just wish there was a concrete way to know what was going on in there!