The upstart ale is made by Alan Thompson, who runs the Old Chimneys Brewery between Bury St.Edmunds and Diss. Alan explained that he was very careful to check in the Good Beer Guide that no other brewery produced a "Bittern". Unfortunately, as Reephams beer of that name is only an occasional brew, it is not listed. So Alan went ahead.
The two brewers are sanguine about the clash of names. As Old Chimneys Bittern is also intented to be just an occasional brew, Alan has offered not to produce it when Reephams Bittern is on the market, which leaves Ted feeling less Bittern about it.