Clearblue Digital OPK low to peak in 6 hours?

I'm wondering if quite else has had this happen. I've had one other cycle where I went straight from low to peak in 24 hours with no high reading between. Usually I have at least one day of high between days of low and peak. I've been using them for every cycle the last nine months. But this cycle was crazy. I tested at 9:30 am 11/16. Negatives strip opk but I could tell it was getting close to positive. But the Clearblue Advanced Digital read low from the same urine sample. I retested at 3:30 pm 11/16. A whole 6 hours later. I got a very clear positive strip opk and I got a peak reading on the Clearblue Advanced Digital from the same sample. It was a good thing I was testing multiple times through the last few days or I would've missed it (although I still got a strong positive strip opk again at 1:30 am 11/17). Anyone else experience this or have any idea why/how this would happen?