My short answer: Either is fine. I'd probably use the version with two "will"s because the sentence is long enough that with only one the implied "re-use" of the first one could get lost.
It is true that in general one should be cautious about using the same word twice in one sentence. But that guideline is less important when talking about short common words, like "is" and "he" and "the" ... and "will".
In a very short sentence, it's common to drop the second "will" on a compound future-tense verb.
Fine: Sally will stand and will give her speech.
Better: Sally will stand and give her speech.
The second is correct because the "will" is understood to apply to both "stand" and "give". It is better because it avoids saying "will" twice in rapid succession.
But in your example, "expand" and "allow" are pretty far apart, and it is easier to see a reader losing track of that first "will". In that case not dropping the second "will" may make the sentence more clear.