Hello, long time no see! (it's been a hell of a year)
Does anyone know how to change the order of Mail accounts in El Capitan? You used to be able to "switch on" the accounts in the Accounts list in System Preferences and have them appear in that order in the Mail accounts lists (and therefore select which was your "default" email account for new messages), but now it seems to be fixated on sorting them in alphabeitcal order, within type (i.e. mail accounts, gmail accounts...).