User can't figure out swap-in deadline for three months

[real-or-random]

When a swap-in is not yet done, but we're not yet in the last month of the 4-month timeout, the user has way of figuring out when it will expire.

This is a genuine report of my personal experience. "Oh damn, this could expire at any moment now! When was the payment made? Was it 3 months ago? Was it 4 months ago? I can't remember exactly because it was months ago. Why don't you just tell me?!"

I was pleased to see that #444 made it such that I will actually learn about the deadline when it's close (1 month), but as a user, I don't even know that I will get this reminder in the future.

Here's a suggestion:

• Always show the deadline under "Ready for swap"
• Add the warning icon when we're close to the deadline