Layer index limit

I'm reviewing the viability of using polyanya for nav mesh generation and pathfinding across a map using procedurally generated terrain chunks. Assuming a singular NavMesh which uses layers to connect adjacent terrain chunks, the `u8` layer index limit for stitching becomes an issue. The chunking algorithm i've designed spawns / despawns adjacent terrain chunks around the characters as they traverse the map but this can lead to more than 255 layers. Is there a reason for the `u8` limit? Could this be increased? Is there a better approach I could take to traverse separate nav meshes rather than attempting to stitch layers together? Happy to submit a PR if they are welcome?