Grouped Calendar inherits individual cal settings

Hi
My site has sections which each have their own calendar of events. On my section pages I show a list of the next 2 months upcoming events, but on the homepage, I just want a widget showing the next 7 days for ALL sections. I have not been able to configure this regardless of the settings I use in my grouped ‘All Sections’ calendar as it inherits the span of the underlying calendars. I suspect you may say “Yes, this is how it’s supposed to work and you will need to create a second ‘set’ of section calendars with 7 day spans then group those.” Is this my only option or is there some way to make the grouped calendar show less events from the underlying calendars?