I’ve proved the theorem:

**Theorem**

- $latex f \mapsto \bigsqcap^{\mathsf{RLD}} f$ and $latex \mathcal{A} \mapsto \Gamma (A ; B) \cap \mathcal{A}$ are mutually inverse bijections between $latex \mathfrak{F} (\Gamma (A ; B))$ and funcoidal reloids.
- These bijections preserve composition.

(The second items is the previously unknown fact.)

and its consequence:

**Theorem** $latex (\mathsf{RLD})_{\Gamma} g \circ (\mathsf{RLD})_{\Gamma} f = (\mathsf{RLD})_{\Gamma} (g \circ f)$ for every composable funcoids $latex f$ and $latex g$.

See this online article for the proofs.