You talking about Manchester by any chance? In my experience it usually damp, but with a shiny glaze of anti-ice fluid. Usually not anything akin to say, for example, a rain shower having passed through. There is no way that there is anything likely to lead to ice accretion on the intake or fan blades. However, rules are rules.......Common sense would say no issue, rules may dictate otherwise. Load an extra 20kg of fuel, stick on the anti-ice and let the company worry about it.