Btw changing mobile number in BOB is a headache process.
They have to first deregister mobile banking and internet banking and updating mobile number.
U have to give 2 3 forms for it
Bro it might be true. Or may be not,try for urself online.
But as far as I understood, they try to skip or postpone the work for that moment,
Suppose if u go with some details or docs, they will sense what u forgot taking to the branch, like if u bring aadhar, they will ask pan, if u take both, they will ask photo, if u take all 3, they will ask passbook
My frd was asked photo for mobile number update, he had to visit next day, but next they didn't took photo.🫠