Let’s suppose I am an ukranian and riding a node, I need to run away with my hardware, how long can my node be offline without informing the situation I am going through to the other nodes I have channels open with, and that my node will be (hopefully) back online in a few days?
To simply put the question, how long can a node be offline without risking loosing the funds on open channels?
Will be good to inform your peers about the situation, being offline.
If they understand the situation will not force close the channels and wait.
If you do not have their contact, you can post your “maintenance” on Amboss Billboard (also you can check there if they have some contact details - see their node page).
But anyway, a channel can stay offline as long as the peer want to keep it like that. So is not a big deal, from LN perspective.
My opinion… just close cooperatively your channels, withdraw the funds into a secured wallet and wipe that node, keep the hardware for later when things start calm down.