Since always. EFTPOS was designed with offline support (signed receipts) as an emergency fallback when the network is down. It’s been like that since the 90s, I know because I’ve been using EFTPOS since then and experienced many outages.

It is capped at $300 per card used and 200 transactions stored (I believe some large merchants can vary this, but not by much), it’s only for temporary failures not multi-hour outages.

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