Kechris's second conjecture on projective unreachable cardinals

Let ${\mathbf{\delta}}^1_{2n+2}$ denote the supremum of the lengths of ${\mathbf{\Delta}}^1_{2n+2}$ pre-well-orderings of ${\mathbb{R}}$. Assume ${\sf{ZF+AD+DC}}$. Kechris's second conjecture. Then ${\mathbf{\delta}}^1_{2n+2}$ is ${\mathbf{\Sigma}}^1_{2n+2}$-unreachable. The supplied context does not report a proof or disproof of this stronger conjecture, so its resolution remains open.