Best practices for monitoring the need for future updates on a theme that I developed?

I recently developed a theme which has been accepted into the WordPress repository. I want to keep this updated for my users. What is the recommended way to monitor the theme’s need for updates?
My guess is that it should be checked for deprecated functions and using debug etc plugins perhaps every time there is a major WordPress core update – is this on the right track?

How often do other developers check their themes and what is the process they use for checking?
Many thanks, I have searched but can’t find this information anywhere.

If the theme repository is anything like the plugins one, content that hasn’t been updated in a while gets hidden, even if it still works. Its probably a good idea to check themes and plugins at least once a year against the latest version, update their meta information, and check them into the repository as an update, even if no functional changes needed to be made. It lets wordpress know you haven’t abandoned it.

(As I have a few plugins in the repository I should really be following my own advice here, but…)