That will be the pool's N Range you are refering to. Look at the Account -> Rewards tab and you'll see it has gone up to 100 hours + which is just over 4 days. The block we just earned took just under 2 days, so if you started at the begining of that block, then your reward will be approximately half what you will earn (proportionately and dependent on pool hashing rate) in blocks earned in 2 days' time if you continue mining with the pool at a steady hashrate throughout that time.
Interesting. I see what you are saying regarding the expected payout. His ramp up time will still be closer to a week though since the shares while canaan was here will drop off before he reaches full reward (our N range will continue to drift toward a week as well until/unless canaan returns).