hodlbod on Nostr: Use a kind 3xxxx and design a subscription status thing. See my PR for notification ...

Use a kind 3xxxx and design a subscription status thing. See my PR for notification services for how it might be done: https://github.com/nostr-protocol/nips/pull/1796/files

This fits the semantics of a "balance" or "subscription" and can be generated on demand in response to a req, or periodically and published to other relays.