In my experience, which may be limited, or skewed somehow, the awkward stage can happen anytime, but for a lot of different reasons, any of which may be: inadequate nutrition, a stress such as illness or weaning, etc.
The first sign (in my observation, again) that they are hitting an awkward phase is that they tend to get a little thin looking over the topline. By that I mean ANY indication of a ridge as opposed to a nice, round look (from above and behind or in front and above).
The belly begins to look bloated, and often this is where people second-guess the feeding, thinking "too much" (hay, feed/fat) and cut down. In my opinion, that is wrong.
I usually start to give MORE feed, more development or growth formulated feed, more beet pulp/more hay and pasture, and the "look" goes away.
If they do growth spurt/awkward on you, it will often manifest as a higher rump (also known as butt-high) that usually goes away within a few months as they front end catches up.
If hooves are not trimmed carefully, the bloaty belly can help exacerbate a splayed hind leg angle. When babies are born with somewhat "off" angles, it is easy to excuse it as being young/growing, but it's a good idea to get the opinion of an experienced farrier and/or veterinarian to help choose the best course of action.
Adequate nutrition can play a part in these things, but proper trimming will help determine what is congenital and what is being caused by growth or any other factor.
Usually things like a weak hip or straight shoulder, ewe neck, etc. are NOT caused by growth spurts, but they can look worse during a growth phase (such as butt high makes an already weak hip look really awful with making the back look weak and poorly coupled, too).
The best thing I can tell you is to feed well in a young horse and you should experience less problem with awkward phases.
The one horse I have here that is going through one now (and went through one last summer) was not with me for three months of her life after she was one month, and they didn't feed like I do.
She returned to me with a HUGE belly, underrun heels/long toes and terribly splayed hind legs. I don't know that the hind legs will ever be fully normal, but we're working on it.
I was pretty disappointed when I clipped her, and am not going to send out a "wet" mare again if I can help it.
Good luck, and I hope this gives you some starting point, and others, too...feel free to pick it apart those that have more experience, I'm always learning, too!
Liz
OH!
