Reviving this topic for something I observed in the field a few days ago: the Langley Bypass seems to carry BC 1A all the way around the city, unlike how TM marks it as staying on the Fraser Highway. This doesn't match up with the Kilometre Inventory, however, which is consistent with the current TM version.
It has a concurrency with BC 10 from Willowbrook to Kwantlen Polytechnic and then rejoins the Fraser Highway to the south.