@zande - That is so true Zande, when you have a pack of bitches, the one "low" on the totem pole may be the last to come in heat in many cases... "want a be's" many times will come in first... depends on the pack.
Ellie is fine 99% if the time, but very occasionally (every couple of months) if she's asleep on someone on the sofa and they move slightly she lets out a very aggressive snarl/snap as described in the article. She then wakes up and looks very confused. It feels like she has no control over it and I wonder if it's when she's in a specific stage of sleep.
Interestingly she has never done this in our bed at night.
We have been training her the "off command" which is rewarded with a treat and that now works well even if she's asleep - she jumps straight off knowing there's a piece of chicken coming her way afterwards!
Sometimes seasons take several cycles to settle down. This is nothing to worry about, just another reason why you should let nature take its natural course and not spay a bitch before it has, and you know she is hormonally fully mature. By which time you will probably have found there is no need to, anyway, because keeping her safe from the boys is no big deal
I found a really excellent method which fixed this quickly. I just give house guests (esp males) a few pieces of chicken and have them freely give it to the pups when they meet them. They LOVE house guests now.
She's very young. It does take some bitches a couple of years (cycles) before they settle into a routine - which is another reason not to neuter them until everything has really settled down !) I wouldn't worry too much, just keep a close eye on her.
She was born 'out of season' - but will probably revert to one proper season a year in time.
@roguecoyote Good for you ! I swear by a Gentle Leader as a training tool. A week or so on one and then a day on a normal collar and lead and they trot along fine. They go back on the GL from time to time just as a refresher. You are controlling their head and that is very important.