Things can go wrong in vital breeding period
In these situations, silage (or preferably, strip grazing silage areas) must be introduced, as well as extra concentrates. Don’t force cows to graze too bare or to go back over grazed areas; this will slow down recovery of growth. Slow down rotations while grass is scarce.
As concentrates are four to five times the price of good quality grass, they should not be used to substitute for grass, but as a supplement when required. But you have what you have at this time of year, and remember that cows have to be fed properly.