As far as his temperament changing, he is still the same dog with family. He has however increased in confidence. He's much more alert and discriminatory towards unfamiliar sounds/people on his turf. He's gotten more serious in that regard. He's very biddable, but has started to exhibit the Mastiff Lean (claiming people/invading space) so if that's a rank driven characteristic we tend to not let it happen.
He's also not a dog park dog. At around 8 months he became easily excitable. Any unbalanced, overly submissive or overexcited dogs become a target. He's quick to jump into any existing confrontation and start/end/enjoy the fight. Keeping him distracted, or really being on him visually is required to call him off, but once he's engaged good luck.
He is social and stable with many other dogs, but these tendencies appear to be environmentally triggered. A particular confined dog park in tends to set him up for failure in this regard - so we rarely go. I do use it however to monitor his growth and development from time to time. How his behavior is socially/how he views rank/dominance with other dogs/obedience proofing and general behavioral observations.
This could also be a reflection of a year old in tact male figuring life out. His fight to bite ratio is very good, but as a bully breed many of the same rules don't apply to him. (Big, strong, pitbull like dogs engaged in a fight/dominance display is not the same as the dominant standard poodle pushing his weight around)
Monitoring and knowing your dog's behavior/triggers is extremely important. People are amazed by his advanced obedience skills, and he makes for an excellent breed representative. I work to ensure that he is calm, stable, and sociable, but also make sure that he is set up for success and monitored closely.
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