It's a serious lack of light, that's what's needed to keep them short & rosette shaped as before.

That's strange as it was in a south west facing window where it got very strong light. In fact I thought maybe it was getting too much so I moved it.

You be surprised how much light Echeveria can take. I know I certainly was when I first started with my succulents :) They love the spots right up in the window where all my "regular" plants fry to a crisp :)

How long ago did you move it?

I'd say about a month ago. It already had changed shape. I thought maybe it had something to do with changing the pot but it is a similar size to the one I replaced. Also, it was at its current location (by bathroom sink) for a long time and kept the same shape. I will move it back to the window to see what happens.

I believe once etiolation occurs it is not reversible although I have heard if you take a cutting or the top of the plant and root it and keep it in enough light it will grow normally.

To echo others, yeah. This is just stretching for light. It's not uncommon to think our succulents are getting more light than they actually are. I was recently reading a story in a succulent book where the author was working with someone who was sure the window was enough light because it had worked in the past for her succulent. She hadnt factored in that over the years the shrubs she had planted outside got tall enough to create some shade over the window! Lol Also, our eyes adjust and we often think things look brighter than they actually are.

Unless your bathroom is really really sunny, it wont be enough light for this desert plant. Not sure you can give it too much light, reasonably speaking. Too intense, yes but you'd notice burn damage or stress coloring.

It's not reversible. The stalk the leaves grow from cant really shrink and the leaves sprout from specfic nodules on the stalk.

However! If you give it enough light it will start to grow more compact at the top again. Then you can cut it after awhile. Just lop the top off. In fact, i see a place there already just under the new growth that you will probably be able to use later. Then let the end callous over and let the stalk sprout some roots. Then plant it in gritty well draining soil in a SMALL pot and water carefully and sparingly.

For now, you'll just have a succulent tree. :D

haha! Yes I do. Thanks for the input everyone!

If you put it in bright light now, as it grows it may get wider more than taller. Its worth noting that many commercial growers use chemicals in addition to lots of light to prevent etoliation or "stretching." Also, more likely in bright light, it may produces offsets which may have that shape.

Mine has elongated... in full sun in the greenhouse. I repotted it would that have cause it? Only 2 out my 12 succulents have done this. Am curious as to why it has occurred ... apart from the sunlight issue?

How did it elongate? You need to post a photo...some succulents grow long stems, but most that 'elongate' do it because of insufficient light. It is difficult to be sure without photo...