Clearblue Digital OPK vs BBT

First off, I'm a huge fan of Clearblue digital opks. They were so helpful for finding my fertile window that lead to 4 pregnancies (one healthy 8 year old, one miscarriage, one healthy 5 and 3 year old). I think they work very well, however, they do have one flaw in that they recommend you stop test after a peak result. In normal circumstances (young, low stress women) I 100% agree, but if there is any stress in your life, or you are in your late 30s (like I am now), there is the occasional chance that your body will have one surge that doesn't initiate ovulation, but then a second (or so) that does and in those less common cases, you will miss your fertile window if you just rely on the digital peak reading. I recommend that you chart bbt if you are concerned that your first surge might not be leading to ovulation. I had 4 previous cycles with predictable peak opk (around cd16) and period (around 12dpo). While I wasn't feeling stressed, Im about to move abroad (in 10 days), so I can't imagine that has affected my cycle. With this last cycle I got a peak on cd17, but then my period at 24dpo. While my bbt didn't exactly support the peak opk, I had faith in it believing I was getting a classic pregnancy stairstep bbt pattern. You can imagine how disappointing it was to have a late period (for once!) and keep getting bfns. In looking at my bbt pattern now (with my consistent luteal phase length and typical ovulation bbts) I'm guessing that I actually ovulated on cd27. (I've attached some previous bbt charts below.) So, I don't want to discourage Clearblue opks because I like how they give you a nice warning that ovulation is coming, but if you suspect that you might have delayed ovulations (for whatever reason) I would highly recommend that you chart bbt as a back-up. It can be confusing at first, but after some cycles, it really does give you valuable information. Best of luck ladies!