can someone tell me is this the teenage phase

Harley is 9 months now and seems to be acting very naughty recently, he will jump up at us on setee and nip if we tell him to get down or usher him off. Jump up for attention and nip when telling him to get down. When on walkes he refuses to leave the park and lies down he will wait till we go over then get up or if we pick him up by the harness he nips. Recall lol something we have always practiced but see another dog he is off or if on lead he will pull to other dogs and if I don't let him play with every dog he sees he will nip at my trousers or lay down. He is doing his bronze certificate at the moment and I'm doing some training and tricks each day would anyone else recommend any thing that I can do with him to help things I know it's just a phase but I feel like we have grounded at a Holt with his training. Any advice would be appreciated

Yup teenage phase alright, keep consistent with the training and don't give in to it he's just pushing boundaries. Also, remember that Staffies are very people orientated so if you ignore him he'll soon get the message.

Start fresh, they tend to lose their memory at this stage and like human teenagers need guidance to keep on the straight and narrow.

I found this invaluable when bringing my two up https://www.doglistener.co.uk/puppies/criticalperiods.shtml they didnt fit 100% but did most of the time, its a great guide. def recomend a read of the rest of the site as well. good luck as I remember it well but it is a short period and actualy good for bonding