Poonen's uniform boundedness conjecture for torsion of Drinfeld modules

Fix $q$, $r\geq 1$, and $d\geq 1$. Let $L$ range over extensions of $F$ of degree at most $d$, and let $\phi$ range over rank-$r$ Drinfeld $A$-modules over $L$. Poonen's Drinfeld-module uniform boundedness conjecture. The cardinalities $\#(^\phi L)_\mathrm{tors}$ are uniformly bounded. For rank $r=2$, equivalently, there is a constant $C>0$ such that whenever $\deg\mathfrak{n}\geq C$ and $[L:F]\leq d$, the curve $Y_1(\mathfrak{n})$ has no $L$-rational points. This is the Drinfeld-module analogue of uniform boundedness for torsion of elliptic curves and abelian varieties. The supplied text gives no resolution.