Vanco Reducing Question

Hi, my 20 yo daughter was lucky enough to get a prescription for vanco 6 months ago (ANI brand, 250mg 4x a day). Its been a miracle and all looks good. She told him 4x a day is hard to remember and he said, to make life easier, she can take 500mg twice a day instead of 250 4x. He’s not reducing the dosage, just prescribing twice a day instead of 4x. As the neurotic mom, I would so much rather her stay on course for another 6 months as Dr. Cox does, since everything is going so well. Does anyone have any imput, either positive or negative, when it came to taking vanco 2x instead of 4x? Thank you.