Considering the registration requirement in the UK is to register all drones above 250g in weight this one seems to have been designed as a loophole.
As it weight 249g you don't have to register with the CAA and as long as you keep it under 400ft altitude and within 150ft from other people and private property you can fly it anywhere where there isn't a local limitation and it's not restricted airspace.
In places where there are limitations e.g. London and other big cities you can fly it on private property.
Please note that in the UK the entity that manages a park or other public spaces can impose its own restrictions e.g. you can't fly drones in Alexandra Palace despite Barnet Council not having a wide ban on drones.
For the most part don't be an idiot the police doesn't enforce these rules for the most part outside westminster where the cops do chase down drone flyers especially around the tourist spots since you aren't allowed to fly anything within 150m of a congested area which is pretty much any spot in central london.
"But your honor. The speed limit is 65 and I was going 64."
"You were exploiting a loophole. You may have been adhering to the letter of the law, but you were in gross violation of its spirit. We don't play games in this courtroom. Your fine is $250 and you owe $437 in court fees."
