> Further, the claimant must possess the land adversely to the actual owner. This means that the adverse possessor cannot be occupying the land with the permission of the owner.

Dave claims that he was given permission to occupy the land by a previous owner, which can complicate matters here. If the current owner took possession more than 20 years ago and insists that permission was not granted, then Dave wins. If they took possession less than 20 years ago, then Dave hasn't been there without permission for long enough, unless there's some duty to inform. Given that the legal dispute started in 2016 the window probably isn't even 27 years: more like 21. And without documentation to establish that he was actually there 27 years ago, it's not looking good for Dave here