Operator’s CPC doesn’t count towards driver’s CPC and vice-versa. I had to take my DCPC less than six months after passing my OCPC.
OCPC will cost around £1,250, less if you do home study, employing an external TM will cost £250+ a month for a one-vehicle operation. Do the maths. Additionally the OCPC isn’t just a useless tick-box exercise, you’ll learn a hell of a lot from doing it yourself.