Arvid - we don't do that anymore nor do I recommend it.
We stick with Leaders/Anchor programs that allow for continued strength/size and allow us to program every area of training with respect to the other.
So you'd do BBB for 2 cycles with 5's PRO. The % is based on your training level - obviously the more experienced you are, the lower the %.
Anchor would be 1 cycle of PR sets and limited supplemental work.