I certainly thought this was settled, but I looked into it out of curiousity to answer David's questions, and the most recent case I can find was 2011 (Watkins v. SunTrust), which is much more recent than I thought. Most were 10-20 years ago (ancient history!). The SunTrust case found that H-8 was ok for same lender refi, but there was a dissenting opinion. So at least one appeals court judge thought the difference mattered in 2011.
I also could find anything that overruled the 2006 7th Circuit opinion that stated H-9 was not an ok replacement for H-8 (lender gave 4 copies of H-9 and 1 of H-8). It's always nice when the court specifically says that TILA doesn't care about common sense.
Handy v. Anchor Mortgage Corp, 200 F.3d 511, 515 (7th Cir.1999).
"Although we are sympathetic to the district court's common-sense observation that “had Mrs. Handy wanted to rescind and looked at her closing documents and found either of [the H-8 or H-9] forms, either one of them would have led her to rescind[ ],†we nevertheless conclude that Anchor's simultaneous provision of both a Form H-8 and a Form H-9 did not meet TILA's clear and conspicuous disclosure requirement, especially with regard to the “effects of rescission.†  TILA does not easily forgive “technical†errors.   See Cowen v. Bank United of Texas, FSB, 70 F.3d 937, 941 (7th Cir.1995) (stating that “hypertechnicality reigns†in TILA cases)."
Maybe not as settled as I thought, at least if you're in Illinois, Wisconsin, or Indiana.
Recap through 2011 here:
https://consumercomplianceoutlook.org/2012/first-quarter/on-the-docket/