1 year out...reflux at night

Hello everyone,
I am 1 year out and 100lbs down. I have a 4cc band that I just got a fill in last week from 3.6 to 4.0.
During the day I am not really struggling, but if I drink something late at night..it tends to come back up during the night. Is this a sign that I am too tight or just that I need to stop drinking so late at night? I have not had to have an unfill as of yet and there will be no more fills as I am full, but I did not want to let it go if its too tight. Any insight I would appreciate!!