Take a look at Mem MD11 F/O lines 575, 641, 643, and 644. Each of these lines should be very senior lines. Each line has intl DHs, long layovers in nice cities and hotels, and mostly, fly one leg a day. These are lines and pairings commuters and non-commuters would like. However, this month each of these lines has at least one AM out and back added randomly during a long block of days off.

Incidently, I'm afraid we'll see more of this as the BLG line spread increases.