It's all depend on IIO. I went to Arlington INS office for interim EAD. The officer said we can't give you interim EAD since VSC is processing your case. I got RFE for EAD. But when i go to Norfolk office, they didn't ask any question.
My opinion is, take the publsihed rules with you, one from I-765 form and another from INS website. It's clearly mention there that one can get interim EAD if it is not approved/denied within 90 days.