Dynamic Interval for Schedule Modelling (repost from Developer)

I'm not sure if this will address what I'm trying to do. i believe the formula would work for a single selected outage start date, but it would not apply my selected (via slicer or parameter) to a group of outages as i'm trying to do. while my data set only shows 5 projects now, my full data model will be consider 100s of projects scheduled over the next 30 years.

While I'm very impressed by PowerBI, this is quite frustrating that it does not seem to have the ability to do this. As i said, I could make this functioning model in excel quite easily - it just wouldnt give me the visualization that i'm looking for.

It feels like my only option may be to create a data set that has every combination of durations that are possible. Not complicated, but certainly alot of adminstrative work to build the data source