Hi Nick,
I wish that your studying Japanese goes well.
If I hear / read "に in this context, I would expect the following verbs like
"おこなわれます / ひらかれます" instead of "です"
But this can be possible and sound natural;
「つぎの かいぎ は いつ おこなわれますか」
「きんようび(に)です」
「では、また きんようび に(あいましょう)」
In the case above, "おこなわれます" is just hidden after "に".
And you can also omit following "です" and say
「きんようびに」
I think it possible because we already heard the verb "おこなわれる" in the question.