@Con-Hennekens
I certainly haven't completely understood everything yet, but I know how track/route-as-track navigation basically works. If you like, we can share our thoughts.
Here is a good example (posted initially by @UwB), the "Maira-Stura Kammstrasse" in the Alps:
https://www.myrouteapp.com/en/social/route/10444583?mode=share
The part between VP 2 and 5 is routable with OSM/TT, but not with HERE:
![MSKS-WebPlanner.jpg](/assets/uploads/files/1738171322462-msks-webplanner.jpg)
The route is stored internally in MRA so that the calculated path is completely modelled (I don't know how this works technically; it's probably similar to Basecamp with hidden SPs).
In MRA NN, the route is therefore displayed in its original shape both in the preview and after opening.
![MSKS-NN.jpg](/assets/uploads/files/1738171355050-msks-nn.jpg)
When it is started for "route-as-track" navigation, it is treated as a track and is not recalculated - not at the beginning or during navigation (white line).
However, a new route (blue line) is calculated, which follows the track as closely as possible. If the route deviates too far from the track, it is displayed in this area as the crow flies, and no information (turn instructions, ETAs, distances) is shown during navigation.
I suspect the issues discussed here arise when you rejoin the route at VP5. The actual path does not have to be re-determined in terms of "re-routing", but something may have to be "re-calculated" to show the adjusted ETAs and distances (and maybe turn instructions as well) - even if "auto-recalc" is turned off.
Do you agree so far? What are your thoughts?