Is there a new version of the used framework, filled with practical but also necessary (security or performance) improvements? Just upgrading often isn't the case. Together we look at the risks and possibilities to perform the upgrade.
Sometimes it requires a bit more then just upgrading the framework and for example also PHP or the entire stack needs to be upgrade. It's then necessary to do a full upgrade and test it.
How tempting it is to combine it with "some" maintenance because your already in the code, my experience is this usually ends with bad results.