There isn't any difficulty with the truth or falsehood of statements about future events.
Consider the two following statements:
(1) There will be a sea battle tomorrow.
(2) There will not be a sea battle tomorrow.
Each of these statements is either true or false. If one is true, then the other is false.
Obviously, we don't know the future, but this is absolutely irrelevant. Most of the time, we also don't know the past. A statement claiming that an event took place is either true of false, and this irrespective of whether we happen to know whether it is true or whether it is false.
Consider the two following statements:
(1) There was a sea battle in 527 BC.
(2) There was not a sea battle in 527 BC.
Again, if our notion of truth is to mean anything, either there was or there was not a sea battle in 527 BC.
If there was, then the first statement is true and the second one is false. If there was not, then the first statement is false and the second one is true.
We don't seem to know of any sea battle taking place in 527 BC, but this is effectively irrelevant because there is a clear distinction between the idea that statements are either true or false, and the idea that we may know and not know whether a statement is true or false. The two notions are semantically independent.
However, there is a logical relation: The fact that anyone knows a statement to be true implies that it is true. The fact that anyone knows a statement to be false implies that it is false.
However, and crucially here, the fact that we don't know whether a statement is true or false doesn't imply anything as to whether it is in fact true or false.
We may even do good logic with statements about the future. For example:
The statement "I know that there will be a sea battle tomorrow" logically implies the statement "There will be a sea battle tomorrow".
This implication is crucial to the meaningfulness of the notion of omniscience.
Using transposition, we can also infer the following:
The falsity of statement "There will be a sea battle tomorrow" logically implies the falsity of the statement "I know that there will be a sea battle tomorrow".
The fact, usually recognised as true, that we cannot know the future, is enough of itself to explain that we don't know today whether the statement "There will be a sea battle tomorrow" is true or not.
There is nothing special in this respect about the future. What applies in this respect to the future, also applies to the whole of reality. That is, we may conceive of statements, and we often do, without knowing whether they are true or false. This applies to the future, to the past, or indeed to the present. My next door neighbour is talking to his daughter on the phone. It may well be true, and it may equally be false. I don't know. But the statement is either true or false. Exactly as it would if it was about a future event instead of being about the present.
And if the above is somehow erroneous, then it should be easy to exhibit a counterexample.
As to Aristotle, we shouldn't believe what people claim as to what his views were unless they provide a quote and a link so that we can make sure the claim is at least plausible.