It was only when checking in at Little Gransden did I see the joining instructions which showed I should have not ventured north of the field. My fault entirely I admit but I would not say it was unprofessional flying.
It is on their airfield info which I assume you carried/studied before you took off? I'm not being high and mighty here as I'm a low time pilot myself but surely you have been taught (and if not why not) to have a look at the airfield you are landing at? It's not you as a low time pilot I'm worried about, it's your instructor.