Don't you mean, you should follow it with big bud until the last 2 weeks before
flush, then change to over drive...i.e. let's say for the sake of argument; ...that your flowering period is 8 weeks to actual harvest (not counting the transition week when you change lights to 12/12 and leave veg ferts or flush...)so, 8 weeks to actual harvest...1st week of flower Add bud blood to your flower nutrient schedule. week 2...NO more Bud blood. you now add Big bud for 4 weeks... 5th week... stop using big bud and add overdrive for 2 weeks...1 week flush with final phase =8 weeks...
...This is what I do, but the weeks of flower w/big bud vary, depending on how many weeks you veg and what type of strain...some strains take longer to finish and some strains are longer in flower due to genetics...
...Is that what you meant cnd 411? I use all these products religously with the exception of the silcon...I just don't need it.

Hilatewood,
Overdrive is used on the last 2 weeks of flowering stage. The flushing week doesn't count.