In 2003 at age 62 I had an early oral cancer found and removed (not HPV related). The docs at a leading CCC gave me the advice regarding alcohol. "Don't even drink the tiny glass of champagne at your daughter's wedding".
Being half-Irish and a bit of a rebel, I followed my own road,sometimes abstaining, etc. After ten years without recurrence I thought I could tolerate two glasses of wine a day, and when I told that to my doc, my future was foretold. "This will activate cancer in the jaw which will go to the roots of teeth and require extraction", that was Sept. 2014. Wow, that got my attention so I shifted to two glasses a week but in January 2015 active cancer was found, the prediction came true and the cancer was surgically removed.
Why am I sharing this information? At the time I was trying to figure out how to deal with alcohol in my life I searched a lot and found little that applied to those of us with OC. I knew my doctor's position and at that time I was not ready to abstain, (guess what-I now have). So, if you are searching for information my best guess is that the safest thing to do is to abstain, but if you don't, going days or weeks between drinks seems to be more important (I doubt anybody has really studied this) than the number of drinks when you do drink.
This only my opinion-I'm not a professional in this area so just remember- "Free advice is worth what you pay for it". Good luck.

My doctor told me that alcohol can cause a recurrence if it was the culprit to begin with; however, given my age at diagnosis, he said alcohol was not the cause, and told me it was ok to continue to drink in moderation. This was also at a leading CCC... who knows! I do try to drink in moderation, and only on weekends, but it's tough giving it up completely for me. Hopefully this isn't a death sentence, but I just feel no one really knows!

Over the years this has been debated many times. Anyone doing a search for the key word alcohol has their pick of any number of threads with many members both pro and con. Personally for me its not worth the risk of another recurrence. Ive seen several survivors who did not give up drinking, they did cut back but not completely. Sadly, these friends are no longer with us as their cancer returned with a vengeance. The same can be said about those patient who cant quit using tobacco, if they continue using it after OC eventually their cancer will return.

Heres more info that may clarify the use of alcohol after OC.

ACS... Alcohol Use and Cancer

NCBI... Alcohol, Tobacco and Oral Cancer

I've been around 3+ years and do think the topic of consuming alcohol posy treatment merits serious consideration, especially if your diagnosis may have implicated alcohol as a cause. In that case, it seems prudent to avoid or severely restrict consuming alcohol.

My diagnosis was HPV and in that case, it seems less clear there is a tie between alcohol and oral cancer. There are little to no scientific studies that indicate alcohol is a factor in cancer recurring. Nobody wants to do anything that causes cancer but personally until I see vetted study results showing the link, I'll keep popping a few brews.