It takes as long as the spring only because they weren't looking. They can stretch the oath that far, they can be disinterested in knowing - but now they know, and so there it is. Elwing of Sirion is twenty-three. Half-man, so fully grown. Sirion is a city of refugees. Elves and Men and, since there are Men, children. Elwing herself has infant children.
They debate whether to send messengers. Debating is allowed, even protracted debating. The Oath, these days, is loud in their minds, and louder when they're pushing it like this, but they drag out the debate for a few months. Messengers will probably be shot on sight. The last time Elwing of Sirion received news of the House of Fëanor it would have been the news that her brothers, twins, aged seven, had not survived the sack of Menegroth.
They send messengers anyway. The messengers are shot on sight. They have good armor, Fëanorian armor, and return home injured but not lethally. Maglor's songs no longer stitch them together. War makes you worse at healing. Maglor's songs are more powerful than ever - he can knock back a wave of approaching enemies, he can make a blade's next touch deadly, he can make them faster and more impervious to danger, but he can no longer do healing.
Maedhros, when he thinks about this, thinks that perhaps there needs to be part of you that is not broken for healing spells to draw on. Or perhaps the Enemy is amused to strip that away first. Perhaps the Enemy finds it suited to the theme as the Oath tugs and yanks and twists them into violence against the lands they once defended and the peoples they once sheltered.
They send messengers to Sirion again. The messengers deliver a plea for the Silmaril, an offer of anything at all in exchange. The messengers do not return at all.
The Enemy is many many hundreds of miles from here but at night Maedhros can hear him in his head. Is it so implausible that I really let you go? the Enemy likes saying. You serve me better free than you ever would have willingly.
The Oath allows them to work slowly. They begin planning the sack of the refugee camp even more slowly than the Oath allows, so slowly that its currents are constantly tugging at them. Any slower and the currents would erode all the things they care about which are not the Oath, and it would be a disaster to go to Sirion once they've been stripped of their capacity to care about anything that is not the Silmaril. So they do not hold out forever. But they work as slowly as they can.
"You look like a mortal," she says. "Mostly because you don't have wings and don't know how fairies work, admittedly, but what else would you be? I don't know what a Vala is so I don't know if they count."
Shiver. "I don't know what else is important to you. I don't want to hurt anyone and nobody but you can make me. - Unless someone else feeds me. There's no fairy food here, if I eat anything that isn't straight out of your hand it'll vassalize me to whoever can claim the food."
"Not very well even when I don't have a broken knee. I can fly. If you don't want me to fly I'd rather try to walk than be carried."
"Specific enough that there's no chance I look away for a second at some point and you're far away finding someone else to get to rescind your orders, general enough that I'm not constraining you from thinking about escape - if I give my word not to escape, that only constrains my actions, but if I give my word not to consider escape, I change my mind itself. Are you the same?"
"Orders can make me think about something but cannot make me not think about something, or want something, or believe something. Why does your word do that?" Fucked up alternate universe gracewings? "I can't fly all that fast, I couldn't be out of earshot that quickly."
The fortress is not glorious, but it is imposing, and it has thick walls and is very very safe. There are people milling anxiously around the ramparts. He explains as they approach. I don't know what she is. I do not think she is of Arda. Don't read her mind or at least don't indicate you've done so.
She doesn't comment on the architecture. She just flutters along, keeping pace with him.
"The temperature's fine. I don't know if you have anything that would fit me," she is after all five feet tall and winged, "but this dress should hold up for a while longer. I could use more food. Plants are better, I think mort- I think some people eat non-plants."
"I have some questions. Answer truthfully and completely. If I say something like 'would you do this?' does that count? Or does it need to be more direct? If I ask you 'is there information you're withholding from me that I'd care about', do you have to use your best model of what I'd care about, can you rationalize? or change what I care about by suddenly doing something I care about significantly more?"
Twitch. "If you say 'would you do this' and don't specify under what conditions it leaves me partly free to imagine conditions on my own but you couldn't accidentally let me to say I'd do something I'd never do. With that phrasing I could use my current model of what you care about, I wouldn't have to think hard about making sure it was good, but I couldn't deliberately worsen my model by anything other than carelessness; I could do anything I wasn't otherwise forbidden to do in the hopes of adjusting my model but I wouldn't have a very long window to do it in before I had to answer."