Why does the relationship not work anymore?

To make it easy to switch time ranges I created selector that let you select among 6 “temporalities”:  this week, this month, this year etc…

It is based on 2 extra tables, one, called “Calendar”  that associates each date with the relevant 6 temporality it can be associated with; and a relationship table that contains all the dates and is associated with the dates in calendar on one side and with the event date in the fact tables (actually with 2 dates, the open date and the close date, hence the 2 lines, one dotted, below)

This worked like a charm until I refreshed the data this morning.

I did not change anything to the data model.

The only thing I did is removing the use of USERELATIONSHIP with 2 measures and remove/restore relationships in the project (at some point there was a glitch in the data load that suggested there might be an issue with those metrics).

But today everything is restored as it was yesterday so I don’t understand why

• The Calendar to AllDates relationship works
• The Fact table to AllDates relationship works
• The Fact table to Calendar relationship does not work anymore

Again, it worked as expected; I could pick a temporality from the Calendar table and filter on the related subset in the fact table.

What could have possibly happened?