TomTom XXL 550M Reference Manual page 13

Tap this button to replan your original route.
This button is shown when you have changed your route by calcula-
ting an alternative.
Recalculate
original
Tap this button to change your route so that it passes a particular
location, perhaps to pick someone up on the way. When you do this,
a marker is shown on the map for the location you choose to travel
via.
Travel via...
You choose the location you want to pass in the same way as you
choose a destination. So you can select from all the same options,
for example: Address, Favorite, Point of Interest and Point on map.
Your XL calculates a new route to your destination that passes the
location you chose. Unlike your final destination, your XL does not
inform you when you pass by this location.
Tap this button to plan a new route. When you plan a new route, the
old one is deleted.
Plan route
Tap this button to delete the current route.
Clear route
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