On a Fixed Time Boxes roadmap, spanning is a statement about a period. If the box you are stretching into has no start and end date, Shorter Loop refuses and says:
That time box has no dates, so a card cannot be stretched into it.
the All products roll-up on an organization roadmap
a theme drill-down
Pick a single product, or leave the drill-down, and the handles come back.
The stretch looked like it worked, then snapped back#
That is the save failing. You will see “Could not save the new span.” The card returns to its last saved width on purpose, so what you see always matches what is stored. Check your connection and try again.Related: How do I make a card span several time boxes?