I am a secondary school teacher, and have been offered a new job which starts on 1st of September 2013. I have received the offer letter which contains confirmation of salary, start date etc. My new school will have received my references which I know are fine. I have to fill in the CRB check form thing and medical questionnaire (these will also be fine.)
My current school are pressing me for my resignation letter, I think so that they can recruit to replace me, but they haven't said this outright. Technically I don't have to resign until May 31st, and don't want to be obstructive, but equally don't want to end up in a difficult position (I.e. jobless!)
So,my question is, is it "safe" to resign on the basis of my offer letter, or should I wait to receive a contract?