Your dashboard’s four headline prediction cards default to 5K / 10K / Half / Marathon on road, but you’re not stuck with those — on the Manage page, under Headline predictions, swap in any distances you like (800m, 1500m, 3K, trail HM, 50K, and so on). Surface options follow the distance you pick — track-only distances can’t be set to road/trail, and half-marathon-and-longer can’t be set to track. Custom distances are projected from your 5K. Saves are instant — refresh your dashboard to see the new picks.
Full explanation: Manage Page in the guide.