Worker bees

At what point (it was recently) did "drone" change meaning?  When I was young, drones were layabouts, lazy do-nothings -- cf. Wodehouse's "Drones Club" with Bertie Wooster as typical member.  Now it seems to mean robotic workers, mindless but endlessly busy -- cubicle drones, office drones, etc.  One new example I noticed and have lost used it for masses of some sort of genuinely hard-working workers -- "construction-site drones" or similar.  L. says she's always thought of drones as busy workers -- the housebound equivalent of worker bees.  I say no -- not that it matters to the metaphoric use what reals bees really do.  They are simply males waiting around for a chance to fertilize some eggs.