Home Assistant limited to 255 entities?

I have a long-standing Home Assistant installation. When I try yo configure the Home Assistant integration for Remote Two, it seems to be limited to 255, entities. I have tried removing the integration and reinstalling it but it consistently only recognised 255 entities. Is this by design?

I could probably live with only 255 of my HA entities showing up in R2 but I would need to be able to select which 255 rather than accept an apparently random subset.