I need your help!!

I am down to the last three weeks before Shamrock, and I need your help tweaking my training schedule for the last few weeks. Here is the dilemma: I have a half marathon this Sunday, but want to run another 22 miler before the marathon. Here is the current plan I made up a few months ago (I have this in a table, but I don't know how to post it on my blog, sorry):

Week 9: Race Preparation (Monday February 23rd – March 1st)
Mon- Rest or cross training
Tues- 12 miles w/ 4 x 1200 m @ 5K race pace; jog 2 minutes in between (VO2 max)
Wed- 7 miles w/6 x 100 m strides (Recovery + speed)
Thur- Rest or cross training
Fri- 12 miles
Sat- Rest or recovery
Sun- 13 miles (Chilly Half marathon race)

Week 10: Race Preparation (Monday March 2nd – March 8th)
Mon- Rest or cross training
Tues -8 miles w/ 5 600 m @ 5K race pace; jog 90 seconds between (VO2 max)
Wed -5 miles (Recovery)
Thu- Rest or cross training
Fri - 8 miles w/6 x 100 m strides
Sat- Rest or cross training
Sun - 22 miles

Week 11: Taper and Race (Monday March 9th - March 15th)
Mon- Rest or cross train
Tues- 7 miles w/ 8 x 100 m strides (General aerobic + speed)
Wed - 8 miles w/ 3 x 1600 m @ 5K race pace jog 2 minutes in between (VO2 max)
Thurs- Rest or cross training
Fri - 5 miles w/ 6 x 100m strides
Sat- Rest or cross training
Sun - 12 miles

Week 12: Taper and Race (Monday March 16th –March 22nd)
Mon -rest
Tues -7 miles 2 miles @ race pace
Thur - Rest
Fri- 5 miles w/6 x 100 m strides
Sat- Rest
Sun - Shamrock Marathon 26.2 miles

My question is, do you think leaving my 22 miler until March 8th is too late? Will there be any physiological benefit. That is two weeks before the marathon vs three. I can't do it the previous week because of Chilly. Any suggestions are welcome.
Hope everyone is having a good week, thanks for reading!