in your area, will it reach down to frost level at any time within a day or two before or after the pour?
if not, the concrete will be OK, but cover it after initial set with a tarp or something. Try to pour it in the morning so it will be stiff before sundown so the tarp does not scuff the surface. You can use hot water in the mix.
if there will be frost, it is possible to protect it, but less trouble to wait for warmer days.
Cornwall is usually less frosty then Perthshire.