I have worked in 3 schools.
Current head will obviously be first reference.
Who do I pick for 2nd?
Headteacher at my first school who gave me amazing cpd, TLR, put me forward as a lead teacher advising other schools but is now retired but I can contact her.
Or my last head who I was a phase leader for and who I have little respect for. She has taken the school from SM to Good though whilst I worked for her. Little respect=little trust to have my back. I left that school for family reasons - nothing to do with her or the job.