Thickening a branch being air layered in the future.

So this summer I wired a few branches on a couple of plants my mom owns with the intention of possibly air layering them next year. My question is; to get the thickest branches as quickly as possible should I air layer them and plant them asap in the spring or should I just let the branches grow on the mother plant until I have happy with the branch/trunks thickness.

The latter is usually faster. Alternatively the layered part can be planted in the ground once you have selected the best roots, usually after one year.