My wife is T1. She hasn't been riding in a while because of a pregnancy and now our toddler. She's ready to get back, but we'll have to start over. Before the pregnancy, she was on Lantis and when we'd ride (MTB), we'd go 30 mins, test her blood, eat half a power bar and that would work perfectly. Now that she's on a pump, we'll have to figure out a new setting (60%) for a longer ride sounds like a good place to start.
It's mostly a matter of vigilence for both of us.