Word among the mids is that girls will no longer have to cut their hair. However, a word of caution - all of your female DI's had to cut their hair. Most of them are still at awkward stages of growing their hair out and are envious of anyone with long hair. They are not happy about the change and if you have long hair, you will attract their attention.
If you are determined to keep your hair long, be prepared for constant scrutiny. Be able to get it up in a perfect bun in virtually no time. You will have extremely little time to shower and do your hair during Indoc. And your female DI's will cut you absolutely no slack.