In the previous version we were able to clone the remote repository and update it to a tagged revision
as you can see the log here, v4.6.0.118 it's the tag of the branch r4.6.0.118
$ hg clone --rev v4.6.0.118 remote_repository_url local_repository
adding changesets
adding manifests
adding file changes
added 199 changesets with 13401 changes to 6466 files
updating to branch r4.6.0.118

But when we updated the plugin to the version 1.38, we couldn't clone the remote repository and update it to a tagged revision
$ hg clone --rev v4.6.0.118 --noupdate remote_repository_url local_repository
adding changesets
adding manifests
adding file changes
added 199 changesets with 13401 changes to 6466 files
[v4.6.0.118] $ hg update --rev v4.6.0.118
abort: unknown revision 'v4.6.0.118'!

So we had to downgrade the mercurial plugin to 1.37 for the time being.