Cassia Rose Heatley
Regarding permission to train elsewhere, I think this is a difficult point too.
You are a full grown adult and a paying customer. You don't need to ask permission. It is your time and money and you spent it like you want.
Telling him you're going to attend a seminar or check another dojo is good manners, nothing more nothing less. Your aikido teacher can't deny you permission not pull the "loyalty" card. He is not your legal guardian and much less your feudal lord and if he tries to behave like one.... run away form that place asap.