No, black/red is 23 (or heavier) gauge used for terminals with screw binding posts. A lot of older buildings still have screw binding posts which use an even thicker rubber coated wire [also black/red]. However - very few of techs carry it so commonly the jumpers are being replaced with Yellow/Blue ones. [As seen in the second photo on feeder 3,(9),10,and 20.]

Typically Yellow/Blue cat3 24 gauge is used for voice and ADSL lines. The jumper wire is typically stored in OSP enclosures.

Bell wants White/Blue cat5 24 gauge to be used for high priority VDSL circuits.

Below is a photo of a 4010 enclosure, here the blue/white jumpers are from techs like me who carry this wire with them, and does not signify a VDSL circuit.

edit: I believe the w/brown in the upper left corner is feeding a pressure transducer but I do not remember.