I brewed an oatmeal stout last Sat. Should I move it to a secondary or leave it in the primary until fermentation is done? Also, how long should I bottle condition it? 4 weeks or can I start drinking it before then?
Thanks,
Dano
Strictly a matter of opinion and personal preference.
My brews spend a week or 10 days in primary (stronger brews somewhat longer) then go into secondary for a few weeks or months (depending on the beer). As many will be quick to tell you, the secondary is an unnecessary step, but I feel I get a better finished beer doing it that way (and not insignificantly, a stubborn 30+ year habit is hard to break).
Seems to me that you can start drinking it after 2 weeks of bottle conditioning under the right circumstances…but I’d be willing to bet that it’ll taste better after 4 to 6 weeks.
I would definitely agree that 4 to 6 weeks of bottle aging would be better. I’ve always found that the extra time in the bottle helps improve the flavor.
Happy Brewing,
Brandon
Also, with regards to transferring it to a secondary… The only time I use a secondary is for fruit and big beers that need more time. I currently have an amber ale that I will bottle after 2 weeks without transferring it to a secondary. Hope this helps.
Brandon
Most styles, especially bigger beers, will benefit from additional conditioning/aging. There are some styles (hefes for example) that are best drunk young & fresh, but they are the exception. Smaller beers generally will improve for 4-6 weeks (or more), plateau for a while, and then slowly degrade. Hop aroma and flavor is one thing that can drop off over longer periods. Oxidation can be an increasing problem if your handling/bottling is not done well. Infections that are minimal or undetectable at the start can become increasingly noticeable with time, etc.
On the other hand, if you brew a bigger, higher-gravity beer; try setting aside some bottles and taste them periodically over months or years. If you have the patience, you’ll be rewarded. Aging beers can bring out some incredible flavor changes. If you go to a good beer bar, ask if they have any vintage beers. Sometimes they’re more expensive, but other times not so much & then it’s a great value & tasting adventure.
I’d just leave it in the primary until the fermentation slows then either transfer it to the secondary or bottle depending upon the gravity. People often make the mistake of bottling the beer when it’s too “green” so let the gravity decide. Once it’s bottled then you can expect between 2-4 weeks for it to be drinkable. Enjoy your efforts! 
I recently finished off a case of Oaked Oatmeal stout myself…the primary was about 2 weeks… the secondary was a full year!! Man was that stuff awesome! I ALWAYS use a secondary for at least a week though. Happy Brewing!
I have a big(1.071OG) stout that was about 2 wk. in the primary (no secondary). Sampling at 2 to 3 weeks after bottling, I thought I had totally screwed up by using too much roasted barley. At 4 to 5 weeks after bottling stored at around 62F the roasted grain bitterness is really mellowing out. If things keep trending as they have so far, that stout should be very tasty at 2 or 3 month old.