Roads scrambed after upgrade/replace

I 've created a straight, one-way road and tried to upgraded it to a highway. Although many “parts” where upgrading fine, some “parts” suddenly decided that they needed some curves :grinning_face_with_smiling_eyes: so this is what happened

A closer look :

Where it should look like this :


I had to delete and rebuild the problematic road “parts”

Both roads, old and new, are one-way 3-lane roads

game version is 9.1.204

Same happened here when I tried to replace the 2-lane with a 3-lane road
Funny thing that the truckers kept on going :slight_smile:

Game version on these screenshots was 9.1.202 I think.