3NT North (matchpoints, Australia). The lead is the ♥9
West wins her ♥A, and says "Well I guess it's all over, red rover".
East says "Rubbish".
West now switches to a spade, setting the contract by two tricks, giving EW an outright top. Any other continuation gives declarer twelve tricks, which would land NS a shared top.
To further complicate matters, EW insist they play suit preference leads in partner's suit, so the spade switch was automatic (though as one commenter noted, ♥9 could be from T9, 97, or 974). However, they didn't bring a system card or pre-alert their unusual leads.
Is West's comment that all continuations are hopeless a defensive concession? If so, has East's rejection of the concession suggested a logical alternative? What is your ruling?
Although a spade switch might seem like the logical choice double-dummy, it's possible that:
1. East led from ♥KT9 (heart continuation required)
2. Declarer has AKxx,KQTx,xxx,xx (club switch stops dummy's clubs vanishing on declarer's hearts and spades)
3. West hadn't considered East's holding (♠AKT9x) likely until the U.I., due to the failure to overcall 1♠.
I'd be inclined to rule +690. Is this too harsh in a club game? Weighted score?