Sources close to the former couple tell TMZ ... Calvin wanted Taylor to meet his parents, who live in the U.K., but Taylor always told him it was too far away.
We're told Calvin was understandably "bewildered and astonished" when he heard about TayTom's visit to meet his mother, Diana ... in the freakin' U.K.!! Remember, Hiddleston's only been in the picture for a few weeks at this point.
What's the rush? One source says Calvin thinks Taylor's cozying up to Tom to lock down a Bond girl role ... IF he becomes the new James Bond, as rumored.