I would LOVE to be able to open source this project at some point, but I also want to be able to make a living off of maintaining it. I've been reading up on some source available licenses such as Polyform, which can contain clauses that trigger the code to go open source at some point. If I get some traction, I'd really like to make a similar commitment where we will open source this in X months/years. Does anyone have experience with this sort of thing? Is this a good idea?

I'm a former Red Hatter, so I'm all too familiar with the revenue hits a product can take when they go open source, but I have no ambition to turn this into a big business, so I think that should be acceptable (unless revenue dips to zero).