FYI, Daring, Dauntless and Diamond are Batch 1. Dragon, Defender and Duncan are Batch 2.
If ships 7 & 8 are ordered (more unlikely than likely at the moment) they would be Batch 3.
And given the noises coming out of places in and around the Government lately, the Armed Forces in general and the Navy in particular may find itself doing with a good deal less. The Type 45, by all accounts, is an excellent warship with a good deal of potential in it as well; 6 ships of the class will not be enough, especially when so much of the rest of the Fleet will not be replaced anyway.