It shows the local road as route 00125 south of Chemin du Ruisseau St Jean
As best as I can tell, "officially" QC 125 disappears at Chemin du Ruisseau St Jean
Same for the GeoBase 9.0 shapefiles dated 2016-08-12.
and then reappears at the QC 158 interchange on A-25.
Unclear which one you mean: the Exit 46 trumpet, or north of there, the at-grade terminus of A-25.
Shapefiles say the trumpet. I found...
QC158 roundabout:* All of it has RTNUMBER1 = 158.
* RTNUMBER2 = 125 from where WB 158 joins the roundabout to where SB "Ancienne Route 18"
(could-be QC125) leaves, and again on the short right-turn movement from where NB "Ancienne Route 18" joins to where EB 158 leaves.
* This would be consistent with 125 S of the roundabout, except that 125 is not marked there until Chemin du Ruisseau St Jean...
East toward the A-25(46) interchange (which incidentally should be relabeled on QCC158):* RTNUMBER1 = 158 & RTNUMBER2 = 125 until hitting the A-25 ramps.
* Then, RTNUMBER1 = 25 RTNUMBER2 = 125 & RTNUMBER3 = 158 on the ramps that would carry the concurrency in either direction.
Northward, we have a triplex.
A-25's N end; at-grade 125/158 split* The ramps in the SW quadrant are just ramps, RTNUMBER1 = 25 only.
* Mainline roads S of here, both NB & SB, are our triplex.
* The junction itself is arranged as a rectangle, as opposed to the triangle we have in OSM.
* Both E/W legs have RTNUMBER1 = 125 only.
* E leg: RTNUMBER1 = 25 only.
* W leg is split ~50/50 into 2 line segments...
* N half of W leg, RTNUMBER1 = 158
and RTENAME1FR = Autoroute 25. ![Tongue :P](https://forum.travelmapping.net/Smileys/default/tongue.gif)
* S half of W leg, RTNUMBER1 = 25 & RTNUMBER2 = 158.