Learn Romanian: Din moment ce ești bolnav, reprogramăm întâlnirea. - Since you are sick, we reschedule the meeting.

While pentru că simply states the cause of an action, din moment ce translates closer to "since" or "seeing that". You use it when the reason is already a known fact (like the person being sick) and you are drawing a logical conclusion from it.

Can I swap din moment ce with de vreme ce in this sentence?

Yes, they are perfectly interchangeable here. Both introduce a known situation used to justify the main action, so De vreme ce ești bolnav means the exact same thing.

Does the din moment ce clause always have to come at the beginning of the sentence?

Not necessarily, but it is the most natural and common order because it sets up the known situation first. You could also say Reprogramăm întâlnirea, din moment ce ești bolnav with no change in meaning.

Why is reprogramăm in the present tense if the actual meeting is in the future?

Just like in English when we say "we are rescheduling", Romanian frequently uses the present tense to indicate a firm, planned action in the near future. It makes the decision feel immediate and certain in response to the illness.