How to rename a tag
First you need to make an alias of the old tag
$ git tag new_tag_name old_tag_name
Then you need to delete the old tag locally
$ git tag -d old_tag_name
Then delete the tag on you remote location - do note there might be several
# Check your remote sources:
$ git remote -v
# The argument (3rd) is your remote location,
# the one you can see with `git remote`. In this example: `origin`
$ git push origin :refs/tags/old_tag_name
And finally you need to add your new and shiny tag to the remote location.
$ git push origin --tags
Repeat this for every remote location.