Gen 3 pokemon get marked as egg encounter when made shiny on pkhex

[DiegoA111234]

I am currently on a platinum save, I migrated pokemon from leafgreen and emerald and when i try to make them shiny they are flagged as legal, but the encounter type gets changed from wild to egg, is this behavior intended? does pkhex do this in an attempt to make a valid shiny PID? is there a way the mon to keep their encounter type and be shiny?