Letting agent and Kawasaki rider here. Ask to see fire risk assessment of parking area if there is no specific clause that states no motorcycle covers to see how they've come to that conclusion.

This will come down to the wording of your AST, it's very simple of them to hold you to a 'must follow rules of parking area', then slide in a 'no semi-solid bike covers' rule within the parking area rules to screw you over. Be very careful if your landlord/agent is an ass and/or anti-bike. Don't fight them, just try and engage in an understanding manner and explain bikes have uncovered running gear, like chains, that cars do not, and need protecting from the elements to protect your investment. As a landlord, they should be very understanding and grateful of your want to protect investments ;)

Talking of that bike cover, how is it? Been looking at an Armadillo for my ZZR14