“Date cannot be edited on Garmin Coach Plans”

As shown in the photo below, I wish to change the Event Date of a race but since there’s a Garmin Coach Plan based on it, I cannot do so on App or on Web (it’s blacked out or doesn’t repose when I click it). Even if I paused the Garmin Plan it’s still no use. Some people said to “Edit Plan” from posts years ago but I can only Pause/ Quit Plan or “Edit Preferences” (which only concern weekly training days but not ending date”. It’s been years and is it Garmin still hasn’t fixed this or am I mistaken?