For me, I did the small mining versions of the mission in like 12 hours or so (across multiple sessions), though to be fair I got 4663 points in the end so wouldn't have taken 12h. All you really need to do is find a one good tin cluster. You need 90 tin to finish the mission, which honestly isn't a lot. We were mining on Bloom, though some people say other planets/moons are better.
Remember, if you find a good cluster, and there's more than you can mine, you can "r_displayinfo 2" in the console to get your in game coordinates, so you can return to the cluster to continue mining it. Or you can just take a box delivery mission and use it as a beacon, drop the mission box at the cluster.
As for the ice, you can just straight up buy it at Ruin station, which is also a drop-off point for the mission. So, super easy. It's usually in short supply, but I've managed to buy like 20 SCU once or twice. 4 SCU is the least you can buy at once and quite easy to nab even with competition around. And again, you just need 90 for the entire event. Or you can mine it in one of the nearby RAB's or asteroid clusters. Or go to Megumi refueling, less competition more ice.
Additionally, if you get 2x8 SCU boxes of ice from buying them, or 24 SCU box from smeltery, and you need to turn in just 6 SCU each for the small mission, do not panic. Just turn in those boxes and the game now sends the excess back to your warehouse. Losing the extra resources, like you did during the last event, is no longer an issue. You'll probably need to refresh the warehouse view to see them tho, that always scares me.
Oh, and if you claim stuff from smeltery and it doesn't show up in your ship, just store the ship and pull it back up. This fixed that particular issue, which happened to us 3 times in a row, 3 times in a row.
