Newly qualified drivers sign ONLY NMP-EUS to start. The depot itself actually covers the whole route from Brum to London, the Bedford line, and the Willesden Relief. The "Old" line via Weedon should be on almost everyone's route card as well. Not too many sign as far as Brum, but it is on one of the links. Some drivers also still sign 321's, and some of those that do, do indeed cover the Scabby Abbey.
As an aside, the 321's that are left (411-417 inclusive, if you wanted to know) are supposed to be staying for the lifetime of the franchise. They'll always have to have at least 2, as the Abbey is currently unable to accomodate a 4 car 350 due to the length of the platforms on that route. Also, 321's are only diagrammed during the week, apart from the one on the Abbey. They usually run in a 12 car set and an 8 car set. The 12 works in to London first thing (the 0620 ex MK is the usual one) and the 8 car set follows a little later, which then stays on the Trinternational terminators all day. Anyway, I digress.
With reference to the other questions you asked...... As far as I am aware, the drivers work very similar hours to the Guards. So that means; earlies/lates rotating with some nights thrown into the mix. But an early can start as early as 0330, and a late can finish around the same time. They also work a four day week (same as Guards) and have a long weekend (fri-sat-sun-mon-tue) every three. LM on the whole aren't too bad to work for (in my admittedly short career so far) and, as long as the work is covered, and people don't take the p***, management seem to leave you alone.
Anything else you wanna know??