Playtest cards in non-sanctioned events = OK
Playtest cards in sanctioned events = not OK
Let's not make this bigger than it is...
Unfortunately this is incorrect outside of the US and has been for some times. Nothing is put in writing and stores won’t say anything directly; but in a choice between keeping their WPN status or running non-sanctioned events with playtest cards..... the event don’t run. It’s a stark choice.