I use the H1 timeframe a lot. It seems that during premarket USA hours the starting time of candles changes. For instance ES will suddenly change its H1 starting time to 9:30. The H1 candles will be

8:00-9:00, 9:00-9:30, 9:30-10:30, 10:30-11:30, 11:30-12:30, 12:30-1:30, 1:30-2:30, 2:30-3:30, 3:30-4:00, 4:00-5:00 and back to normal.

This behavior is super odd. I see this across a basket of symbols, GC will suddenly start at 9:20 AM ET, or SI will start at 9:25 AM, affecting all candles during the USA session.

How can we disable this and have candles started at normal intervals? This really makes H4 charts look strange too.