Randomly ovulating early by 4/5 days??

C

So I continued to test with OPK through when I had positive OPKs the last 3 cycles (CD 15&16)and it’s been flat negative- I know OPKs don’t confirm ovulation or anything it was just so weird I had my peak OPK this cycle on CD11- I haven’t had under a 30 day cycle since I came off birth control 2 years ago and the last 3 cycles were 31/32 days... what do you guys think??