Don't know if it's a test or permanent but at 3:45am the modem was inaccessible for about a minute and came back online. I checked the modem and noticed that the modem is synced on three upstream channels instead of 1.
Speed tests currently benchmark the 40/2 plan as 40/4 and the 20/1 plan as 20/2
Eastlink has confirmed they are indeed testing upstream channel bonding now.