Brighton is in East Sussex, and that is an excellent, if expensive, location for escorts (IMO). You could search for that city specifically. Otherwise, there aren't a lot of large towns in East Sussex, so fewer punting options.
The SE region covers a strange area all round the sector south and west of London, so not always helpful if you are looking for a local SP. It is similar with the ITV area that covers Oxford and Milton Keynes as well as the obvious south coast citiies. It can be frustrating to find a promising SP, only to discover that she is a 100 miles away.