I'm in a similar position, I do everything that is required of me but ensure that I always have an 'under the radar' project in which I develop something to make a number of users' lives easier or I work on improving something in my area, which since we're predominantly open source and change-resistant means that there's a lot to improve 🙂

It's not that my bosses aren't supportive- if I want time to train they'll give it to me without so much as a blink, but I like to have a few things on the go and having some things in the back of my mind that I can pick up when I have a few moments or when I need to take a break (a change is as good as a break afterall!) Plus it really helps with that 'going the extra mile' bit of the PDR for bonuses 😎