Predicament with class start dates

I have a great opportunity that I am considering, but it would require a work commitment through September of next year. The opportunity fits into my long term goals perfectly (i.e., it would help prepare me for the career that I want post b school, which is working as an equities research analyst) as it would give me significant exposure to the markets that I want to cover. I was planning on applying this fall and then in theory would matriculate next September. The catch is that I wouldn't be able to attend class until late September. So, is this a "no-go" for applying this year if I really want to do the opportunity as most schools start the first week in September? Also, I am 29 now, will be 30 when I apply this fall, and would be 31 when I matriculate. If I have to wait a year because of the dates, then I would be one year older when I apply (31 years old). Does this change my chances much of being accepted? I know I would be at a slight disadvantage at 30, but would 31 be much of a difference from 30? I have the "why xyz school, why now," part down in the application, its just if the age is a big factor then I may not take the opportunity. Any thoughts or suggestions would be very helpful.