Not sure which brit gymnasts are planning significant upgrades, and although I see a lot of potential there for Downie #2 I think GB might likely be fighting for 4th with Romania, and could be a really tough battle if Ponor, Izbasa and Iordache are on that team, if Russia has Komova with some upgrades, a consistent enough Afan and Paseka, and Mustafina leading the way they will be tough to beat for anyone aside from the US. Plus there's China who's won team silver in 2014 and 2015, the most recent without Yao Jinnan. Looking to 2020 though I totally see GB remaining up there and being a more solid medal contender, the development and depth seems to be stronger in GB these days than in Romania and Russia, I mean although all are fantastic gymnasts, Russia is likely to have 4 of the 5 women on the team again that they had in London and Romania 3 of the 5, maybe 4 depending on how things go for Bulimar.
How I'd see things going
1.USA
2.China
3.Russia
4.Romania (even though they have to qualify still I'd day this would be a likely outcome, although I'd be crying for a week if they managed a bronze)
5.GB