I'm expecting that in 2019 interest in self-hosting will increase because between government regulation and misguided faith in AI I don't see the problems which Facebook and Twitter have being easily resolved by any silver bullet solution.
Often after people have used the fediverse for a while they want to try hosting their own instance.
In the UK context I expect that in February/March Twitter will become an unbearable stream of brexit fights and screaming centrists. These days you only have to utter the wrong AI trigger phrase and your account gets suspended, so I think there will be lots of people swearing at particular politicians and then having their accounts suspended and showing up in the fediverse that way.
I'll try to keep the brexit stuff to a minimum, and behind CW. It's bound to be mostly boring Westminster village obsessions. If a revolutionary situation emerges though that could be worth reporting upon. Things like an attempted coup are maybe possible.