Is this natural?
It has been a month since the deadline submission and a month before the program starts.
I don't think it is because you can't say "It has been a month before the program starts", because it doesn't start yet. Someone suggests me that it sounds OK, but in writing the tenses should be the same. Therefore, the correct sentence will be:
It has been a month since the deadline of the submission and a month before the program has started.
This sounds even more unnatural for me. Because that means you say: "It has been a month before the program has started". Since I don't want to split the sentence, the best way I can think of is using an equivocal contraction:
It's been a month since the deadline of the submission and a month before the program starts.
It's for the former is it has and for the latter is it is. But I highly suspect that this equivocal will be accepted.
Best Answer
You need to express the past event:
and the future event:
Simple present will do, as you are talking about a scheduled event (See CopperKettle's answer here).
Don't be tempted to mash them together!
For improved understanding, the "only one more" helps to clarify that you are talking about two different months. The bit in italics is where you would express your "attitude" or "view" towards the upcoming time frame - "still another" / "even another" / "one more"/ "just one" / ... - there are lots of options.