Sorry not RTFT, but seen some news shows with this subject on stating that he's the kings son so should get the same security, however, I don't think, during her reign, that the queens children had the same as Charles as next in line to the throne did they?
Also, as has been said time and time again, he's not a working royal, he may have a dad who has 24/7 security detail, but he'll get the security that is assigned to him via the official routes when he's in the UK.
I find his entitlement and general attitude stinks - throwing his toys out of the pram because he's not got his own way