If you want to be noticed and climb, a surplus of teachers in your school is probably the best kind of situation. It means you have more time to work on stuff that gets you noticed positively by a wider range of KPs and SLs. Ask to lead committees or school-wide projects. Present at open classrooms. Go for courses and share relevant learning with your department during internal PD sessions. Basically, look at the KRAs for your subgrade and beef up your portfolio of work in the non-T&L areas (assuming your T&L is already sorted and solid and you have time and mental bandwidth to work on other areas - don't bother trying to climb if your T&L still cannot make it). Be higher profile and be noticed, but don't be obnoxious. If you are noticed to be reliably performing beyond your current grade, you will obviously be given good performance grades and probably promoted.