The update we recently had in beta is now live. This update fixes a bug that would cause events to get queried twice when a calendar source was set to “Don’t show items unless the calendar is filtered” or when the option to only fetch events when the date range changes was set to “no” and either “Don’t show items unless the calendar is filtered” or “Include resource and status filters” was enabled for a source.
Those two options are described here: https://docs.dayback.com/article/137-speed