We have discovered a typo on a computer generated disclosure for Reg CC which conflicts with our approved policy and our handout brochures. It agrees with the general daily practice of the bank, (next day availability) but said that funds on new acounts would be available by the 2nd business day instead of the 11th business day.

Since the policy, lobby notices, and brochures say one thing and this says another, would revising this notice to correct the typo require 30 day advance notification since it does not expedite the funds availability, or would it simply be viewed as correcting a typo on this document since all others say the 11th business day?

IMO it would not require a 30-day notice because you would simply be correcting a bona fide error so that the disclosure matches your policy.