I’d start applying now - Get as much information as you can too - then if you don’t have something by jobs-fair time, you’ll know what to look/ask for. But the pick of the jobs will go early on, so you’ll also have a better choice now.
We have a short ‘Jobs’ chapter in the new edition of the book too that outlines the basics.
Try some of the independent operators: they usually have a jobs section on their websites - Ski Beat for example are recruiting now.
Natives.co.uk is a very good starting point too.