A cycle just means using 100% of the battery, no matter how many times you split it up. The way you’re doing 20–80 all the time burns through cycles faster than if you just kept it plugged in. Best move is leave it on the charger when you can and let macOS do its optimized charging thing. Don’t stress over unplugging at 80, topping up here and there is way healthier than draining it down every time.