^ There's no set number of hours. It's based on when you go into withdrawals. You need to wait till you feel withdrawal symptoms to take the bupe or risk precipitated w/d. I've had times where I was good to go in 8-12 hours other times I've waited 24 & precipitated.
Basically wait till you have at least minor if not the beginnings of full on w/d's.
IE. some minor leg cramps, yawning, stomach upset, runny nose, might be considered minor & good enough, really depends on the person. For me my minor symptoms usually start with leg cramps, yawning & stomach upset.
Proceeding to hardcore stomach cramping, horrid bone/muscle aches, urge for bowel movements, passing out but not sleeping (if you know what I mean? hard to describe, might be because I'm on other meds as well), for me the 2nd set of symptoms would be full on w/d's.
I've precipitated by waiting for minor w/d's but never precipitated if I waited for full on w/d's. I know it's hard to due but it beats the hell out of precipitating yourself & regretting the fuck out of it.
Just to let you know this is from past experience & lots of it,

but I'm sure my memory serves me right on this one.
I haven't used sub's in a long time as I'm in Pain Management now. Well I was, we'll see Monday if I still am, due to some fucked up shit that they called a suicide attempt but seeing as I'm still getting pain meds, just at lower doses from the Hospital that discharged me, I should be fine.
Not sure how Pneumonia complications & taking some tylenol at a low enough dose that NAC easily reversed it with no damage is a suicide attempt but that's irrelevant to your question just me bitching.
