My primitives (Shetlands and Shetland x Castlemilk Moorits) have all scanned for singles this year, but I had no grass to flush them on. Looking at the grass now I am glad as they will be able to rear them with no problems
Having said that, to me it looks like they have no grass now, but they have barely touched their hay in over a week, 13 sheep and I reckon they have eaten 2 flaps from a small bale all week, so they must be getting enough grass over the course of a day?