After registering a new version of my package with JuliaRegistrator, tagbot reported the following issue with METADATA.jl:
This is because the repository has moved.
However I am not sure why this matters because the package is only for julia>=0.7. Despite the error, the tag was actually performed and the new version is available in Pkg (in Julia 1.1).
But I have made a PR to change the repository URL in METADATA.jl:
Then I realised that there is about a month worth of unmerged PR in METADATA.jl.