Edit: South doubled 1S, sorry I forgot that in the initial posting.
MPs. EW play weak NT with 5cM, short club.
Written bidding is in use. At West's second turn to call, she writes "2", then pauses and scribbles out the "2". South questions whether this is OK and the TD is called over. TD says that the bid hasn't been made yet as no denomination was
West calls 1NT, 15-16, and East raises to 3NT. After the hand (result 3NT=), North queries whether the 3NT call is taking advantage of the UI - he feels that the East hand is not worth more than an invite.
How do you rule? It seems to come down to: is 2NT a LA, and could 3NT be demonstrably suggested by the UI? (When asked why she bid 3NT, East said "15 + 9 = 24 which is game".)
ahydra