Half taxed - that’s a lot of gain. Nice investment.
If you liquidate in early 2016 and immediately invest in a student-owned 529 before you declare assets for FAFSA, you’ll get the best of everything: the gain won’t be included in 2015 income, the asset will be considered a parent asset for FAFSA purposes, and there won’t be any legal or ethical shades of gray regarding converting a UTMA asset.
BTW, do you know the UTMA age of majority in your state? If your child is there, legally he/she is entitled to full control of the money.