Josh,
Always disturbing when there appears to be a disconnect among medical staff. My military Uro goes with 6 wks after TURBT to begin BCG. However, Dr Lamm, considered one of the authorities on BCG, indicates 2-3 wks after surgery on his webpage. Whole point is to give your bladder a chance to fully heal from any tumor resection and/or biopsies before exposing it to BCG. I believe you'll find the timeframe all over the map, but suspect 4-6 wks seems the norm for many...kind of depends on the extent of your surgery.
12/15 - Diagnosed Ta HG, 1.5cm Pap, Focal CIS
3/16 - Began BCG following NCCN and SWOG guidelines
2/19 - Ta HG recurrence and CIS/Ta HG in right kidney/ureter
2/19 - Nephroureterectomy to remove right kidney/ureter
9/19 - BCGx33 completed
2/20 - Invasive HG urothelial pT2 in prostate stroma