Hi,

Seeing you modded this route just before me, I may have broken 552 at the Treglio roundabout, https://www.openstreetmap.org/way/364117986
Certainly did not sort the 2x552 route members as there are just too many, 1209 on 1 of the 552s. Recommended is max 300 (super routes may be solution to think about).

The problem here was there were 2 roundabouts mapped on top of each other. One had the turn restrictions and the other the Flixbus links. Deleted latter and moved route links to the remaining one. (one classed as service, one as unclassified at that as well, for years).

So you're aware.
Ciao