A quick flick through the handbook doing some rough planning last night, it's interesting to see how some days/weekends have a surfeit of quality races on. A few standout examples:

6th April: Coledale Horseshoe, Howgills (English champs), Dungeon Ghyll, Pendle
27th April: 3 Peaks, Mourne Highline (Brit champs) - then on the Sunday - Kinder Downfall and London Marathon.
3rd August: Borrowdale, Creag Dubh (Brit Champs)
7th September: Grisedale Horseshoe (Eng champs), Ben Nevis, Braemar gathering (race for the Queen, and a fair wedge!)

Elsewhere, 3 shires clashes with the final English champs race again. The good thing is most of these races have enough of a following to survive on the same weekend as a big competitor, maybe spreading the field across a few races means everyone's happy and gets a run! And for your smaller more local races happening on the same day there's a chance of a newer face to get a good result (or get hoovered up by a gnarled pot hunter with a taste for cheap wine!)