Please see the offline routing guide, it also contains info for how to change the BRouter profiles:
“Navigation: offline rerouting happens when you leave the current route and trigger a rerouting (automatic or manual), skip the next waypoint, avoid road blocks, etc. while navigating without internet connection. The route is calculated from your current location to the existing route (based on navigation type). Only this small part of the route will be recalculated and merged with the previously planned route. This ensures, that the rest of the route remains as initially planned.”
Details about routing in navigation and the suggested change exist in this topic.
Changing manually route waypoints or parameters in navigation, the whole route is calculated.
BRouter may had problem calculating the small rerouting part (with your profile changes),
but the whole route calculation worked successfully.