Peak hour 'extra' buses for the main routes, and the buses are often supplied from a different depot to the main buses used for a route. The buses used in this are called Euro buses surprisingly enough. They operate Monday-Friday only and most of them are based in Broadstone, though some, like for the ultra snobby 46A have Euros supplied by the home depot(Donnybrook).

It's quite like duty 208/2 here, 8 buses are used all day for the 8, and 208/2 is the 9th bus and operates in the morning and evenings to try and improve the reliability not to mention the capacity of the route, usually something needing a service or maintenance attention will be used in the mornings, and then something else will be used in the evenings, hence why you find the likes of 99 and 00 VWLs on the 8 a lot in the evenings, these are the buses used for 208/2.