Exactly! That's what I meant by "possibly both, but only one at a time". At the moment you're in group (a), but might shift to group (b) later. I'd guess that if and when that shift occurs, we'd lose you as a paid user, regardless of whether we had an open-source version or not. This way at least you get an easier transition, and you'd still be using 'ShareLaTeX' which helps us from a brand recognition POV.