I don't think the change is linear here. Industrial revolution pushed people behind desks because human still had brains while machines were dumb (sic). Then desk jobs were split between computerized backend and social interface done by people; this is what is gonna fall soon. Comptuers can now listen and answer to you; gather real world analog / organic data; rather than only dealing with structured data as since the 60s.

Also, lots societies needs don't even require Alpha Go level of AI; and computer will make these tasks automatic. And these class of worker won't beat machines logic until a deep learning (sic sic) phase.