Congrats BB, I see you just turned Master!
Now you av. will float for a while, going up with a lesser good round, so you might be tempted to protect it (or your ego) by stopping play before completion. No need to do so, as said above.
I've played close to 200 Master rounds, still far from the margin, and in my average of 64.83 there are only rounds of 67 and better (33 for 9 holes). All the others are long forgotten.
BTW, if you'd play tournaments you'd receive double XPs, helping you to level-up faster. You know the continuous-days-played bonus?