Hi @zivhimmel ,
Based on my research, The reason scheduled refresh takes longer is because PBI smooths scheduled refresh so AS Engine and Gateway is not flooded with request. PBI doesn't do smoothing for on-demand refresh.
Such as if you set scheduled refresh at 9:00 am, it may start at 9:14 am, and end in 9:16 am, so seems it refresh 10 - 15 min, but if execute an on-demand refresh at 9:00 am, it will start right now and may end in only few minutes. This document also mentioned :
Note also that the configured refresh time might not be the exact time when Power BI starts the next scheduled process. Power BI starts scheduled refreshes on a best effort basis. The target is to initiate the refresh within 15 minutes of the scheduled time slot, but a delay of up to one hour can occur if the service can't allocate the required resources sooner.
If you needs the report be ready by certain time, schedule the refresh ahead of the time or execute on-demand refresh.
Community Support Team _ Dong Li
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