If you knicked them I would think (but don't know for sure) that you should probably start them now. Besides drying out the embryo is susecptible with an open seed coat. Maybe it's possible to store them in a sealed baggie of soil or moist sand in the fridge? I have no idea what zone you are in but they can go out when it warms up. The seeds germinate super fast, sometimes it only takes a day. You can keep the seedlings in pots inside with good lighting. If they get too long you could always pinch them back until it's time for them to go out.

There is no need to nick Heavenly Blue seeds. A 4 hr. soak is all they need. They germinate very easily. I would do this: do nothing but store them in an air tight plastic bag and put them in a room temperature drawer or the like until you are ready for them.

You'll need to go ahead and start them since you nicked them; as Karyn pointed out they're susceptible to drying out and infection once their protective coat has been breached. The good news is that as long as your temperature is staying above freezing they'll be OK. They will concentrate on making roots, and not grow upwards very much until the temperature warms up.