deployer 7 info deploying HEAD

[jasperf]

When we see info deploying HEAD on deployment:

dep deploy staging
[staging] info deploying HEAD                                                                                                                                                                          
task deploy:setup
task deploy:lock
task deploy:release
task deploy:update_code
task deploy:check_env
task deploy:shared
task deploy:writable
task deploy:vendors
...

does that mean the default branch (main or master often) is used? Does not seem clear to me here.