How far in advance do you book your next Disney vacation? Do you book it as soon as you know your dates or do you wait for codes or promotions to be announced? Do you book and then rebook if something better comes up?

Last time I booked a few months in advance during the free dining program since BF and I were discussing going on vacation and it just happened to work out. This time around we have a full year and a half month until our trip but since the packages are out and I have some gc's buring a hole in my pocket I am wondering if I should book so that we have a guaranteed vacation planned or should I wait in case a good promo is announced. We did not preplan or book a vacation this year (was going to cali wine country but due to a change in jobs that isn't happening) and we are missing out on a vacation because of it (wasn't prebooked and so he won't take vacation right now). So now I'm nervous and obsessive over our vacation for next year.