In this case, I can set BarOffset = ET + 9.5 * 60.
From the zorro help file.
BarOffset Bar start time offset in minutes. Bars and frames normally start at a date/time boundary; f.i. 60-minute bars start at every full hour, and daily bars start at UTC midnight. This can be changed with BarOffset. For daily bars, BarOffset determines the UTC minute into the day when the candle opens, and can be used for setting the bar begin to a certain time zone.
