Reservists will be doing AT; BZN to MPA and back, maybe one towline per year for currency. No formation trg required, very basic ATP-56 procedures only.
Full-timers will be doing anchor AR (sic) over the North Sea or flying the sim, with maybe a trail or two for a handful of the CO's best mates each year; all planning provided by the Jeppesen-powered Ops team.
As for conversion to glass cockpit and FBW - if it was difficult then wouldn't the aircraft manufacturers build steam-powered analogue systems still, and wouldn't all the major airlines be flying VC10s?