At my last job we had a version of our on-prem product where the company sold a super extension for a version that was supposed to go out of support. We had a small team (I think three people) whose only responsibility it was to ensure that version was supported, pipelines worked and we're ready to ship a big fix at needed. That was their responsibility but as long as that was covered they were allowed to work in their spare time on what they wanted as long as they saw value for the company in it. It was a good bargain. Everyone else was grateful the small team was doing the dirty work and the maintenance team was delighted they could use the remaining time working on things that had always bugged them, do research, etc. This was a few years ago and I forgot details but I vaguely remember that we got some really cool improvements and research from them. The people on that team also were really excellent and self-motivating which helped make this a success but also more expensive.
