According to the info here the new moon shouldn’t be sited till the night of the 9th making the tenth the first day of the new Jewish month. Either the second month(Heshvan) or the first(Tishri) depending on if the fall feasts must occur after the equinox.

 

If it is Heshvan the 10th of the month(entering the ark) would be the 19th with the 17th of the month (rains start falling) on the 26th.

 

If it is Tishri that is starting then the 10th and 11th would be Trumpets then the 19th would be Yom Kippur and then the 24th - 31st should be Tabernacles.

 

Paul

 

also my post here http://www.fivedoves.com/letters/sep2010/paulw911.htm the final date for the trib to start using prophetic months would then be the 27th of Oct which would be the new date for Heshvan 18. and the final date using non prophetic (alternating) months would be Nov. 17 or 18 for Kislev 10 depending on the sighting of the moon being on the 7th or 8th of Nov. now if the coming month is Tishri (I based the numbers on the post above on a 9/11 start to Tishri) then the 27th would be Tishri 18 and the 17th or 18th Nov would be Heshvan 10.

 

http://www.timeanddate.com/worldclock/astronomy.html?obj=moon&n=110