Just today I’ve got the idea of the below conjecture:
Definition I call funcoidal such reloid $latex \nu$ that
$latex \mathcal{X} \times^{\mathsf{RLD}} \mathcal{Y} \not\asymp \nu \Rightarrow \\ \exists \mathcal{X}’ \in \mathfrak{F}^{\mathrm{Base} ( \mathcal{X})} \setminus \{ 0 \}, \mathcal{Y}’ \in \mathfrak{F}^{\mathrm{Base} ( \mathcal{Y})} \setminus \{ 0 \} : ( \mathcal{X}’ \sqsubseteq \mathcal{X} \wedge \mathcal{Y}’ \sqsubseteq \mathcal{Y} \wedge \mathcal{X}’ \times^{\mathsf{RLD}} \mathcal{Y}’ \sqsubseteq \nu)$
for every $latex \mathcal{X} \in \mathfrak{F}^{\mathrm{Src}\, \nu}$, $latex \mathcal{Y} \in \mathfrak{F}^{\mathrm{Dst}\, \nu}$.
Easy to prove proposition:
Proposition A reloid $latex \nu$ is funcoidal iff $latex x \times^{\mathsf{RLD}} y \not\asymp \nu \Rightarrow x \times^{\mathsf{RLD}} y \sqsubseteq \nu$ for every ultrafilters $latex x$ and $latex y$ on respective sets.
Conjecture $latex ( \mathsf{RLD})_{\mathrm{in}}$ is a bijection from $latex \mathsf{FCD}( A ; B)$ to the set of funcoidal reloids from $latex A$ to $latex B$.