If so, December predates Conformer, so you're talking about the sconv model, which is the model I was complaining about upthread - it was very polarizing with users, and despite the theoretical WER improvements, the errors were much more catastrophic than the model that preceded it.
In either case, I'm constantly making improvements - I'm in the middle of a retrain that fixes some of the biggest issues (such as misrecognizing some short commands as numbers), and I've done a lot of other work recently that has really polished up the experience with the existing model.