MAC members and guests have entered via the employee security line, and I don't think that would have changed today, so they can easily turn a blind eye (but I don't think they will).

But seriously, things should improve pretty quickly. As OP said, equipment from the old lines has to be moved over, and kinks worked out. Sucks for travellers this week, but it should not automatically mean that some weeks down the road things won't be decently smooth.

If it's still a mess in 30-45 days (though then that is peak Spring Break time, so a tough period anyway...), then perhaps they've made a serious mistake in this consolidated TSA scheme.