SPOILERS || Quest support

[Virida]

For the quest "Maybe now's a good time to check in on the newest member of Outpost One..." and "Spring is here, and you’re feeling a bit restless…" It references another AI Osa (i think that was their name) and visiting Outpost 3. I haven't seen nor know about Outpost 3 past the message decrypting. Have I missed something? I'm rather confused.

Yeah that is sadly currently a problem that will be addressed in the site recode where the quest system will be updated a bit. Here are summaries for the quest parts you missed (they can all also be found on discord):

HW21 questline:
Communications with outpost 3 have been established and you volunteer to be the first to visit, together with Robert. Upon arrival you quickly realise that outpost 3 is nothing like outpost 1. The only person willing to talk to you is Carol Pethe, the head scientist who also sent the initial message. She shows nothing but disdain for Robert and during a visit to their communications room you see evidence that their outpost might have dismantled their own ash-unit. Robert investigates and indeed finds the damaged android hidden in an unused lab. He also finds evidence of extensive damage to the factory level of outpost 3. You sent Robert back to outpost 1 to report because you both feel it is not safe for the android to stay. You remain and help Carol with some experiments.

Solstice 21 questline:
A severe storm caused you to be stuck in outpost 3 for far longer than you feel comfortable with and you are glad to be back home. After some light-hearted fun involving an intense snowball fight and lovely warm beverages and cookies, Robert approaches you regarding a rescue operation for the AI in outpost 3, dubbed Oxa. Packing a load of presents and Solstice cheer into an ECV Sherman and you set out to return to outpost 3. While Sherman distracts the scientists in the cafeteria, you manage to find Oxa and hide them in the ECV and manage to bring them safely back to outpost 1 where the other androids help repair the damage done by Carol and her people.