London Borough of Islington  v SHCLG and Maxwell Estates 2019 EWHC 2691:  The case related the 4-year period necessary to establish immunity against enforcement and therefore lawfulness for a change of use to use as a dwelling house.  The court held that no ‘presumption of immunity’ applied during a period of renovations within the 4-year period in this case because of an intention to resume letting the flat. During the time that the flat was empty, the LPA could not enforce and therefore the time period for immunity had stopped running.