I oak last. What I mean is, after primary, I allow the wine to clear and of course rack whenever lees are 1/4" thick or after about 60 days. Once the wine is clear, and no longer dropping lees at all after 60 days, then it's ready for oaking and bulk aging. I keep it on the oak until the taste is just slightly too much oak (as it mellows with some aging) and then bottle it. I like two ounces per 6 gallons of chips, but your taste might vary. It also depends on how tannic and dark the wine is- some blackberry recipes are light and fruity, and don't stand up well to oaking. Mine is darker and more heavy bodies, and plays well with oak.