While there were some "early" releases of refunds for taxpayers claiming EITC and ACTC, the date the IRS still gives for these is March 3 "for most", though they mention some may receive them earlier.
There isn't any way to know what, if any, reason there is that some are released sooner and others later or any way to really predict, either.
If you still haven't seen a change by the given March 3 date, you could try reaching out to the IRS at 1-800-829-1040.