SEPM v14 Deployment Issues

I'v recently upgraded my SEPM to v14. Initially i could push deploy the upgrades out to any clients already managed in SEPM.

However over the last couple of weeks the push deployment method of upgrading clients has stopped working.

Each agent accepts the new agent version but the install does not take place.

My work around is to export the package to an exe file and run the install manually. But when you have to upgrade as many clients as i do the idea of doing this all manually is not an ideal solution.

All clients meet minimum requirements for the ugprade.

Please advise if you need any more information.