it's a terrible way of carrying on..if they are "so busy" then they should employ someone to specifically deal with these enquiries as it appears they are loosing a lot of business on this issue alone...i think in this instance, the only way to "get through" is hit them in the pocket, then you'll see them getting in contact with you pretty sharpish
It's a pity really, I wanted to look into doing CPL ME rating/Night rating and hour building...