I don’t think there’s any kind of mission that is completable for 4 early players that isn’t completable for a late-game player.
Or they might just be “community events” Elite:Dangerous style. Those mostly just consist of many players working towards a single goal that doesn’t really require coordination or closer cooperation. Stuff like “Space station X needs n thousand Ys delivered during next week”.
They are probably so busy on patching that the most likely scenario is that they put the community events aside for now! 
The official statement was some time after the release of NEXT. I’m not sure where I saw that one week first, but I can’t remember it being included in any official statements. They knew full well that they would be busy patching for the first month or so.
Personnaly I don’t think it’s a big deal. We are currently all so busy finding out new things (mostly bugs but oh well…) on legacy saves, or new starts that I can’t really hold it against them…
We’ve got 1.51 & 1.52… I think they are just working thei socks out for us!
Imagine a community event completely bugged? Nahh-… let’s have some patience! 
Totally agree! Let em fix all the bugs first, before we worry about the weekly community events.
What’s important to me is the building parts being fixed
How do you get quicksilver? I have not seen any mention of it in-game?
Edit: never mind, reddit answered my question.