I think it should be changed.
Corruption - 18 hours (I'm biased, I work ~12 per day).
Reset - 20 mins (Should be 15 minutes if it stays 10 for corruption)
Capture - 3 days (Should be 1 day if it stays 10 for corruption)
My Reasons:
Corruption: You shouldn't be able to corrupt the sigil over the course of a workday, but it happens all the time. Extend it by 8 hours so everybody has a chance to save the sigils.
Reset - 30 minutes is a long time. The fact of the matter is that factions are only alive when the sigils are up and moving. It should be very difficult to take the towns without guarding them heavily.
Capture - 3 days is fine if you spent 18 hours guarding sigils closely. If the 10 hour timer is kept, it should be one. If you can corrupt it while I'm at work, you should only be able to keep it for a day so I can try again.
EDIT: n00bitry ftw!