I was in Ayutthaya last year for this holiday and when my mate and I tried to buy a few cases of beer from Lotus the sales lady said 'No buy till tomorrow'.
On the other hand, in the foodpark outside of the Lotus, they sold me a can of Singha.
7/11 selling beer on 22- Family Mart not- Queen's park Plaza on 22 as mentioned on post before has 2 open as of last night and also tonight- might have to knock to get in.