I think this is sensationalised - it looks like they only waited about a week after cancellation before they started unplugging them.

But I can't find any easy information on the contract they had with Flock, but it could well take a week for Flock to be able to respond properly after working out what to do with lawyers etc. The article says that the account management team had been in touch... so... I think this is just a PR piece for the police chief to look 'hard'.