Thought I would share what I found out:
"When HELOCs are renewed before their maturity date, new disclosures are not required including rescission unless the renewal includes an increase in the line. We find this authority not in 226.15, which is the most logical place since it covers rescission but in the commentary to 226.5b(1). (Comments 2 and 3) Here is the citation:
12 CFR 226.5(b)(1)
Changes to home equity plans entered into on or after November 7, 1989. Section 226.9(c) applies if, by written agreement under § 226.5b(f)(3)(iii), a creditor changes the terms of a home equity plan--entered into on or after November 7, 1989--at or before its scheduled expiration, for example, by renewing a plan on different terms. A new plan results, however, if the plan is renewed (with or without changes to the terms) after the scheduled expiration. The new plan is subject to all open-end credit rules, including §§ 226.5b, 226.6, and 226.15.
Transition rules and renewals of preexisting plans. The requirements of this section do not apply to home equity plans entered into before November 7, 1989. The requirements of this section also do not apply if the original consumer, on or after November 7, 1989, renews a plan entered into prior to that date (with or without changes to the terms). If, on or after November 7, 1989, a security interest in the consumer's dwelling is added to a line of credit entered into before that date, the substantive restrictions of this section apply for the remainder of the plan but no new disclosures are required under this section."