Create a project, setup semantic release and release a version. A shortcut is to create project and create a git tag+release with name v1.0.0 on the latest commit.
Just clone the project (stay on the main branch) and run aem up. This crashes pretty quickly with error:

Hostname/IP does not match certificate's altnames: Host: v1.0.0--my-helix-project--adobe.hlx.page. is not in the cert's altnames: DNS:developer.adobe.com, DNS:www.adobe.io, DNS:adobe.io, DNS:udp.adobe.io, DNS:*.developer.adobe.com, DNS:dev.adobe.com, DNS:*.adobe.io, DNS:developers.adobe.com, DNS:*.developers.adobe.com, DNS:www.developer.adobe.com, DNS:www.developers.adobe.com

A quick inspection took me to: https://github.com/adobe/helix-cli/blob/main/src/git-utils.js#L151-L163
The tag is returned because it matches the commit sha instead of the main branch. And of course v.1.0.0 is not valid in the subdomain host.

3 options:

1. get rid of the tag logic - not sure when we would need it... the probability that the tag name contains a dot is pretty high
2. move the branch logic before the tag logic - if you are in a valid branch, no need to check for something else
3. document we do not support semantic-release at project level