Hi again Sally, yes the waiting is a darned nuisance isn't it. You just want to get in and see the Endo and start to feel better, do you have an appointment yet....I think you were also waiting for a water deprivation test too?
One thing my GP did for me was make sure I had all the blood tests he thought I needed prior to seeing my Endo for the first time, to make sure that there were as few delays as possible for diagnosis. It sounds like if you have something flagged on your MRI then you must be part way to knowing more. In the area I live there is a local pituitary support group (Solent) who meet a few times a year, might be worth getting along to your local one if they happen to be meeting - as it happens the Solent one is meeting this coming Saturday if you are in this area....unlikely probably

Are you on any treatments yet, Hydrocortisone or anything? I had the constant weeing for a time but luckily it went away on its own a few months I had my tumour removed, I didn't get much sleep for weeks, so I know how you feel