Bamboo does not support SCP-like urls in Git

This URL:

git@host.com:magicalpanda/AtlassianTestRepo.git

will be ok for git, but it will fail with Bamboo because it will try to push it through proxy and to do that, it will add port. Port is not allowed with SCP notation in Git.
The workaround for this is to use an URL with username expansion:

git@host.com:~/magicalpanda/AtlassianTestRepo.git