Started Zwift up today, did the update, and clicked on the button to activate the higher levels (not the one to start off at 25). I’ve been at 25 for ages. But my ride started with the counter at 25. After finishing my ride I restarted Zwift and noticed that in the settings page there is a grayed out button that says 25 >> 43. I guess I should be at level 43. Does that gray button un-gray itself at some point (maybe when the counter gets to the next level)?
What that prompt did was enable a higher rate of exp gain until you hit the set level (In your case level 43) Zwift insider did a great job at explaining this in detail >Here is a link to that<