If I have some recent training and PRs (other than the 600m time trial) I could answer it. But I'll say that this goal is certainly feasible.
Workouts that indicate that goal could be anything to be honest.
When I first ran 1:56, I was running about 40 miles a week (was 60mpw during XC and 70mpw during the summer, though.) I was running a lot of workouts at mile pace and finishing with some nearly all out 150's. I could also run about 51-52 for 400m, though.
shortly before I ran 1:56 we ran a workout of 3x400m with 8min rest in 55, 55, 57.
I was also doing hard progression runs finishing at faster than 10k pace for the last 2-3 miles.
This was early in my season though (end of outdoor) so I didn't really start to do 800m centric workouts until a month or two later. But I will b glad to answer questions and help out.