The bidding went :
N E S W
-- 1♠ 2NT 3♠
5♣ 5♠ ?
The agreement was to play 2NT as 2 lowest unbid suits, either very weak or very strong.
So now here we are, stucked with a guess.
Seems to me that either Pass, X or 6♣ are possible calls. . .
But since partner's 5♣ seems weak, looks like 6♣ would be rather unlikely to make.
Thus I think the question is whether we should make some move to show that we in fact have the stronger version of 2NT overcall...
But a X might fetch us a 5♠X = or 6♣X -3
(Switch the vul and perhaps it's easier to X since we don't mind partner bidding 6? Or did he have that option at all?)
What do you think we should do?
By the way do you agree with the initial 2NT overcall?

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