It's hard today but nearly there!
8d Officer takes the wrong regiment- should be less stupid (8) ?????T?R
2d I'm on the phone, being stuck on the train? (8) I?????L?
and for 1a Pretended to have passed out of hearing (7) fainted or feinted??
i've gone for 'rewording' because the bit about making a change is next to the 'lucrative' part of the clue which indicates (at least to me) that 'rewarding' needs to be modified