William Lane Craig, in an interview, explains that he thinks it is fundamentally misconceived to think that there is a puzzle, on A-theory, about how God could know the future if it were unreal. He suggests instead that God’s knowledge of the future is just an innate property which he has. God does not know the future a posteriori, by scientia visionis; instead God just has the property of knowing all and only true propositions, and since there are true propositions about the future God knows them. Craig explains:
The idea that the facts about the future have to be real in order to be known is based upon this perceptualist model of divine cognition, and that’s as I say, very anthropomorphic to think of God as up there looking down, seeing what is going to happen. Rather, God as an unembodied mind, doesn’t really have anything like perceptions because he has no sense organs… God’s knowledge is more like the knowledge of an innate infinite mind, which has the essential property of knowing only and all true propositions… If you are enamored with this perceptualist model, of perception,… what I’ll say in that case is that propositions exist in the present, and so God can just look at the proposition and see what its truth value is.
In response, I would say that the problem is not that facts about the future have to be real in order to be known per se, but, rather, that facts about the future have to be true in order to be known. However, there is no way for some fact about the future to be true if it refers to that which is in no sense real (for then there is no sufficient reason why it is true).
Perhaps this is yet another reason why the A-theorist who wants to affirm that God knows the future cannot accept the principle of sufficient reason (dovetailing on a recent argument from Pruss which has attracted some attention here and here).