If the overage exceeds the trip guarantee you'll get from sub, then yes - take the overage. In most cases that's probably the best option.
If you're talking about basic 6 hour hub turn trips, it's not going to take much to get you over 6 hours of overage. If they extend you 24 hours and bring you back to join the normal hub turn cycle, then you'd be talking about 6-ish more hours at 150% plus an extra duty period at 3.5 CH.
If your conflicted trip was longer, you'd have to do the math and see which paid more.