CPMB medical screening haircut

can I dont cut my hair? are there any loopholes? or die die must cut hair??

Today I receive letter from mindef telling me to come down to cpmb for medical screening

Im a 21 yr old mtf on hrt coming close to 2 years with hair of shoulder length with no letter of gender dysphoria from a doctor plus my hair looks v nice rn and I dont wanna cut it :(