I fear, Jerry, this was not written by an actual British person. The attempts at the slang are not at all convincing, though elements of it are correct. For a start, it mixes regional elements from different parts of the country in a rather   odd way. Mind you, it may have been written by a Brit ironically parodying our own speech. Or possibly written by a Brit ironically parodying an American trying to parody Brit-speak. You just never know, do you, me old china, sithee.