Custom Automations - "Timeline Start Date" won't work

Hi there, I am new to and trying to create a custom automation that triggers the duplication of an item to a separate board before the timeline start date approaches.

My recipe is: 1 day before Timeline Start Date arrives, duplicate the item and move item to Weekly Checklist Board

For some reason, when I click on “Timeline Start Date” from the drop-down menu it automatically switches to “Timeline End Date” no matter what I try. Is this a bug or is there something I’m missing?

Any help would be greatly appreciated! Thanks!