Saudi multi entry business visa

I have a 6 month multi-entry business visa for Saudi Arabia, with duration of stay on each entry of 30 days. Two questions:

1) does the 6 months validity start from date of issue, or date of first entry?

2) Do I have 30 days stay for each arrival, even if I arrive within a few days of the end of the 180 day validity? e.g. if I were to arrive on the last day of the visa's validity (depending on the answer to question 1) could I stay in country for 30 days from that date.

Any advice very gratefully received, I've googled and googled and can't get a clear answer. I've even asked on the way out of country but couldn't make myself understood.

1) Day of entry
2) Yes if you arrive 2 days before the end of visa validity you should have 30 days.

1-day of issue and not entry cause I've experienced it first hand....
2-not sure...you'll have to ask jawaazat once you're here....