For sure. The interlock kit prevents that as when installed in place, you physically can't have both breakers on.
Damn this thread. I was going to put in 10 circuit bypass generator box but now and thinking maybe an interlock would do. I have a newer Square D 200 amp so can order an interlock for it. So, now have to ponder some.
So, with a total bypass how do you know when power is back on? See if neighbors are lighted again?