Leave question

I’m new to the Army and I took HBL during AIT, putting me in the hole by -.5 leave days. I’m finally back in the positives again and I have 9.5 days saved up and I was planning on taking 7 days this summer to go back home. But my supervisor just told me that I’m supposed to have 10 days of leave available to me at all times and I won’t be able to take leave if my balance drops under 10 days. Does it state that in any regulation that I’m required to keep 10 days credit at all times?