The UK government is spending millions in trying to retain teachers. The solution is simple. When a teacher applies for a job the school should be able to apply to the goverment to pay that teacher's wages directly. This way if you are on UP3 the school will emply you instead of hiring cheap ECTs/NQTs.
No other profession in the public sector is so parsimonious. You're an experienced doctor? Great we will pay you. You are an expeienced nurse? Great we will pay you. You are an experienced teacher? No you are not valued and we will hire an ECT. Complete joke. When I was an NQT I could easily get an interview. Now I am an experienced and talented teacher I suddenly don't get interviews. I still stay with my current school but if I ever have to leave I will join a supply agency and ask for £150 a day. If no one is prepared to pay it then fine guess I will be another teacher leaving the profession.