I was able to climb on the bike last night for a couple hours. It took about 15 minutes to climb into zone 2 but I was able to hold it there with ease. I was able to mix things up by changing my cadence. Every 10min or so I would switch chainrings. Big chainring low cadence. Small chainring high cadence. So I would just focus on 10min blocks of time instead of thinking about how much more.
Today I have the afternoon off so I am going do a 3hr ride.
Stats - 2hrs, 139bpm avg, zone 2 time 120minutes