Since when did 26 become "older"? Man, I feel ancient!
But, seriously,Zickos has a good point about getting into clubs.
On the other hand, if the club thing isn't an obstacle, then this could be a great opportunity for learning from more experienced players. I have not been in this situation but if it looks like there is a chance of your getting into this band, then I would take a few minutes and sit with them, see what their goals are, how they operate and what they would expect from you. Find out as much as you can up front and see if you're compatible. If your visions don't match up, it's okay to turn it down and look for something that suits you better. I don't think it's necessarily an age thing as long as everyone is headed in the same direction and knows where that is from the start. Just keep an open mind.
Good luck and let us know how it goes.