Just to provide some closure, I had a very positive conversation with the school earlier today and we have been able to share our point of view and have agreed a constructive route forward that works for both sides. I look forward to continuing to rent from them, at least until I can find a share in something later this year (hopefully).
For a number of fully valid reasons, I don't think it's right to add further details, other than to note I really value the way that the school have listened to my questions and explained their perspective. I am sure things could have been done differently on both sides, but I have to hold my own hand up here and say that I shouldn't have assumed that using these forums as a sounding board before speaking to the school first would be the best first step. Instead, I should have picked up the phone. Now that I have done so, I've got clarity and reassurance that really helps me: it's much easier to digest rules if you understand the motivating factors behind them. Equally, I am sure that my asking questions has been useful feedback for the school too. Mea culpa for not having that direct conversation to begin with.
From my perspective, I'm very happy and keen that the situation has been resolved and I can move on with building my hours and progressing with my flying. Queue the strong winds, low clouds and heavy rain!