PERM LC

Hi everyone, does anyone have experience with an I-140 that was initially filed under regular processing and then upgraded to Premium Processing about a month later? In my case, the I-140 was upgraded to Premium Processing, and it was approved the next day. However, we’re not sure whether the approval was processed under Premium Processing or regular processing, and even the attorney is not sure. If the case was approved under regular processing before the Premium Processing upgrade was effective, would the Premium Processing fee be refunded? Also, is there any way to confirm whether the approval was processed under Premium Processing or regular processing? Any insights or similar experiences would be greatly appreciated. Thank you!