Beyond what average can one typically guarantee themselves entry into any second year program? Do the cutoffs get into the 10s?

for going from science I to kin II requires a high average (10.5)
for going from science I to h. sci II requires a high average (at least 8, the higher the better)

almost all other 4 year programs have cutoffs in the 6-7 area.
Once you are above the cutoff you are guaranteed to be accepted into the level 2 program.

you should ontact someone from the science department to confirm since these averages are from what I remember from a few years ago. They could have changed. Also you can check the undergraduate calendar.