1. E/W claim "Stop" was used before 5♣, N/S claim they did not see any Stop-card
2. Agreed BIT before X, N/S claim maximum 30 sec, E/W claim it was at least a minute
The lead was a club and 12 tricks was made (as you can see, a heart-lead would beat the slam). Both N/S and E/W are strong players. N/S are semiregular partners, but as far as I know they did not have any relevant agreements.
The match was played privately (early stage of qualification for national teams championship) and a TD was called after play ended. E/W questioned the 5♠ call after Souths hesitation/BIT (they argued that North had to pass after the UI). The TD polled 4 players, all bid 5♠, but one commented that he considered passing. The TD let the score stand (6♠N=) and E/W appealed.
The appeal is finished (I was in the committee), since it will be published on the federation pages and it has created an unexpected amount of discussion on Facebook etc. I think it is OK to also present it here. The AC made some additional polls, but first I present the case as it was given to us. Apart from the facts presented above there were some arguments from both sides along the lines you would expect (I can elaborate a little, but there was no info about systemic agreements etc.). Note that East passed in first hand and then bid 5♣ on his second turn, making this an unusual position.
How would you rule?
John