I have fished cranks all the way to ice up (in fact in skim ice). The key is to slow down as the water temps drop. By slow I mean .8 to 1 mph. So slow that stick baits hardly wiggle, so slow that lead core line goes down at about a 45 degree angle. Remember as the water gets colder the metabolism of the fish goes down. They don’t have to eat as often, they are more selective about what they are going to bite and they are not willing to expend a lot of energy and chase down a meal. Cold = Slow!