brew doctor warning: not on the default git origin branch despite being on main

[unitof]

Homebrew seems to think twilio/brew tap is not on the default branch, even when I have just tapped it with all default settings.

I can reproduce this every time:

▶ brew tap twilio/brew
==> Tapping twilio/brew
Cloning into '/opt/homebrew/Library/Taps/twilio/homebrew-brew'...
remote: Enumerating objects: 929, done.
remote: Counting objects: 100% (491/491), done.
remote: Compressing objects: 100% (209/209), done.
remote: Total 929 (delta 420), reused 334 (delta 280), pack-reused 438 (from 1)
Receiving objects: 100% (929/929), 116.24 KiB | 4.84 MiB/s, done.
Resolving deltas: 100% (529/529), done.
Tapped 70 formulae (88 files, 219.5KB).

▶ brew doctor
Please note that these warnings are just used to help the Homebrew maintainers
with debugging if you file an issue. If everything you use Homebrew for is
working fine: please don't worry or file an issue; just ignore this. Thanks!

Warning: Some taps are not on the default git origin branch and may not receive
updates. If this is a surprise to you, check out the default branch with:
  git -C $(brew --repo twilio/brew) checkout main

▶ git -C $(brew --repo twilio/brew) checkout main
warning: refname 'main' is ambiguous.
Already on 'main'
Your branch is up to date with 'origin/main'.

▶ brew doctor
Please note that these warnings are just used to help the Homebrew maintainers
with debugging if you file an issue. If everything you use Homebrew for is
working fine: please don't worry or file an issue; just ignore this. Thanks!

Warning: Some taps are not on the default git origin branch and may not receive
updates. If this is a surprise to you, check out the default branch with:
  git -C $(brew --repo twilio/brew) checkout main

▶ brew untap twilio/brew
Untapping twilio/brew...
Untapped 70 formulae (88 files, 219.7KB).

▶ brew doctor
Your system is ready to brew.

Confirming I am indeed on main in the tap repo:

~ ▶ brew tap twilio/brew
==> Tapping twilio/brew
Cloning into '/opt/homebrew/Library/Taps/twilio/homebrew-brew'...
remote: Enumerating objects: 929, done.
remote: Counting objects: 100% (491/491), done.
remote: Compressing objects: 100% (209/209), done.
Receiving objects: 100% (929/929), 116.24 KiB | 5.81 MiB/s, done.
remote: Total 929 (delta 420), reused 334 (delta 280), pack-reused 438 (from 1)
Resolving deltas: 100% (529/529), done.
Tapped 70 formulae (88 files, 219.5KB).

~ ▶ cd $(brew --repo twilio/brew)

homebrew-brew ▶ git branch
* main
* 
homebrew-brew ▶ git branch -vv
* main 5b71bff [origin/main] Release 5.22.7
* 
homebrew-brew ▶ git branch -avv
* main                                  5b71bff [origin/main] Release 5.22.7
  remotes/origin/HEAD                   -> origin/main
  remotes/origin/aws-s3-migration       2d065ce fix: update urls
  remotes/origin/aws-s3-migration-1     486e978 fix: updating cloudfront path
  remotes/origin/correct-regex          9c19a4b fix: corrected version patter
  remotes/origin/correct-regex-pattern  13deeb3 fix: corrected version pattern to include double digit in version
  remotes/origin/draft-release-main     7483f05 Release 2.34.0
  remotes/origin/main                   5b71bff Release 5.22.7
  remotes/origin/master                 01eab75 fix: provide useful error for migrating from `master` to `main` while upgrading
  remotes/origin/release-feature-branch 566818c Release 2.25.0

I suspect the issue may have something to do with the warning: refname 'main' is ambiguous. coming from the git -C $(brew --repo twilio/brew) checkout main recommended by brew doctor. I believe that is coming from Git, but I don't see why main would be ambiguous.