Tray

Where packets wait and where change collects. A packet is this coin bought by a vend. It sits in the tray until the next vend dispenses it to the wallet that triggered its vend. After six later vends it is stale and burns. Change is the dust and positive spread every fill leaves. It burns with the next stale packet.

Expiry by trade count

Nothing here runs on a clock. A packet does not expire after an hour or a day. It expires after six vends. In heavy volume six vends can pass in minutes. In a quiet market a packet can sit a long time without going stale, because no vends happen to age it. The tray's speed is the market's speed.

Dispensing is automatic. The recipient is the wallet whose curve trade completed the turn. It does nothing to receive the packet. If that wallet's token account is gone and the transfer fails, the packet stays and ages like any other.