Am looking for an estimate of the snow depth either at the lodge or the Monument 78/83 trail head
Blackwall Peak snow pillow, 1934 m elevation:
Currently showing slightly lower than long-term average, and more or less the same as last year. Check back closer to your trip date.
You can also check the Gibson Pass ski area snow report for a estmate of snow on the ground closer to your target elevation
Finally, the Allison Pass DriveBC webcam conditions will also be relevant.