As the developer, you should have nothing to do with Gitpan. It will (eventually) take care of itself as you make releases to CPAN. Do not make your dev repo a fork of the Gitpan repo.
Gitpan is not intended as a development repository. It's a reorganization of historical releases to make them available in a consistent manner across all distributions. The only time it has value to a developer is if you want to fill in gaps in the history of your development repository. Like if at some point in the past a new repo was started but the old repo was not imported, Gitpan can be used to fill in the old history so you have something.
Gitpan is not updating because the original import was done using a prototype that required a lot of babying to make it work. It had no logging and could very easily wedge itself. I started a rewrite but did not finish it. It's in the "rewrite" branch if anyone wants to work on it. Right now I have $work and Test::Builder2 sucking down my time.