Personally I try and feed enough for the day. I found that with 24/7 feed, too much is wasted feed. When I lock them up at night, I check the feed bowl. If a lot is left over, I feed less the next day, if it is bare, I feed more. It is rather surprising how this is not real consistent as in this many birds, this much feed.
Feed tends to be a major expense of birds (not considering the coop/run.) Smells often come from wasted feed, and of course, vermin are drawn to a free feed source.
You will find that people do this numerous ways. Some provide feed 24/7 which I do if we are going to be gone for a few days. Some like me, only enough for the day. To each his own.
Mrs K