I flew with a B737NG operator. The acceleration call was "Bug UP." There were many cadets in the mix, but the error was not limited to them. You guessed it; there were enough Flaps UP selected (F1 takeoffs) that the SOP was changed. F5 was the new standard and the call changed. I can't remember what to. Previous types in the company had fixed speed schedules and so the call was 210kts on previous types.
I then went to another growing airline which was in transition of models in exactly the same way, even F1 takeoffs. I told my earlier story and was met by black stares. Hm. The Boeing SOP ws "Bug UP" so that was that. I wonder why Boeing didn't think of an alternative e.g. "UP speed."