503 error for expired logins (because of a 10-day long contest)

[kevinsogo]

• A less scary 503 page so contestants won't feel like they did anything wrong or illegal/disallowed in the rules. (Baka matakot silang ma-disqualify haha)
• (Up for discussion) instead of a 5xx error, a 4xx error?
• (Up for discussion) extend expiry? (need to think about potential security risks. But maybe up to 11 days is fine.)

I suppose contestants regularly encounter this because most of them will just stay logged in.