Tolley has featured regularly in the Wales set-up and keeps his place in the squad under new boss Brian Flynn, who was installed when John Toshack took over the senior side.
But the move puts Tolley out of the re-arranged league clash against Bury, unless he is released by the Welsh FA.
Wales under-21s take on Germany in their group six UEFA Championship qualifier at the Racecourse.
Wales are currently lying fourth in the group with a win (1-0 v Azerbaijan), loss (0-2 v England) and draw
(2-2 v Poland) from their three games. England top the table with 10 points.
Town's other young Welsh wizard, David Edwards, misses out on a call-up.
As for Lyng, he travels to the infamous La Manga training resort with the Irish under 19 squad to take part in a 4-team tournament featuring Norway, Czech Republic and Denmark.
Lyng will be unavailable for Town action between February 6th and 12th, putting him out of contention for the games against Bury and Grimsby.