Of course, as is virtually inescapable at the USPTO, with every general rule there come exceptions. For example, according to 37 CFR 1.311(b), an authorization to charge the issue fee (37 CFR 1.18) to a deposit account may be filed in an individual application only after the mailing of the notice of allowance. 37 CFR 1.25(b) also makes clear that a general authorization made prior to the mailing of a notice of allowance does not apply to issue fees under 37 CFR 1.18. Thus, you must affirmatively do something after receiving a notice of allowance to accept the offer of a patent.