The Route Optimizer from yesterday now has a second engine to choose from: Mapbox Optimization. Same job of sorting your stops into an efficient order, but for most stores it's free, one whole day of routing counts as a single request and the first 100,000 a month are free, so you're realistically looking at zero.

You pick the engine under Route Optimizer → Settings. OpenRouteService, the one you had yesterday, is still there and works fine. Mapbox just gives you more headroom without a bill, so it's a good one to start with. Setup is a one-time thing: a free Mapbox account, a quick form to switch on Optimization v2, then paste your access token. The full walkthrough is in the setup guide.