Snoop I found at that age mine was very affected by unusual noises in the night, much more on guard and protecting of the household (ie growing up and aware of adult role in standing up and defending territory) So, could it have been the Fireworks - noises that you didn't register that he heard, or fox in the garden?
tbh I didn't find that neutering at 9 months made much difference to the protectiveness and adolescent high jinx (he was still full of beans and curiosity), and I wonder whether it made him actually a bit more of a scaredy cat. It just reduced the running off after ladies and the humping marking behaviour.
So be aware that so called "adolescent" behaviour doesn't go away just because you neuter. I gave mine the neutering injection just in case, it is being in renewed in Jan, hopefully I will have a clear picture then whether it has been good or bad for him.
I found a bit of reassurance and reminding him what the routine was, safe spaces etc helped my adolescent puppy settle at night. Changes in the day of one sort of another (there are always changes in a normal household it cannot be perfect) might have set him off, and with reassurance to self settle he will start sleeping through again. Mine was out of a crate at that age. Would that help? I found a cosy room, dog proofed to some extent, water, a area he could pee on if he was desperate (but almost never ever did) all helped to make the downstairs a place he slept through in. Ours never woke till we came down, often that was 7.30, 8 at weekend, but more usually 7am when we got up in term. I think the space he had ( room 4.5m x 3.5) made that more likely than if he had been in a crate. He could get up in the night find a new sleep place get a drink and resettle if necessary without us.