The Expanse

Future Guy claims that the Xindi were only testing their weapon design this time, and that a much more powerful version is being prepared. By doing this the Xindi have allowed Earth a chance to beef up its defences and prepare a retaliation mission. And suppose the weapon hadn't worked? Then Earth would have captured both the intact weapon and the pilot. Whereas if they had tested it on some uninhabited planet somewhere, then waited until the big version was ready to attack Earth, they would have been able to inflict far more damage.

The writers are a little cagey about the timeframe of this episode, having characters talk about it being a long trip back to Earth without being specific. It's also been a while since we got a good reference as to how far the ship is from Earth - 90 light years in "Dead Stop". But to make this episode work, we would either have to assume that the ship has been heading back towards Earth at close to top speed ever since then, or that something like a year passed offscreen as they headed back. It will be interesting to see what the next date they give us is.