I played with a partner I don't play with much agreeing to play a variable NT 10-12 is some seats and 14-17 in others depending on vulnerability with 2 completely different systems.
I picked up a 3235 17 count in first seat and was evaluating if to strong for 1N and if 1C pass 2N was correct but decided to open 1N in 1st seat and heard partner explain 10-12. I quickly decided that I would have treat partners response as if we were responding to a strong NT. Left hand opponent doubled and partner bid 2H which shows hearts and spades in a weak NT with a transfer as a strong NT. To not give partner any ethical issues I alerted as hearts and spades and bid 2S that ended the auction. 2S made 5 with partners 4414 hand when 3N is going down most of the time. I called director after hand to explain situation since I did not think opponents would think of calling director. Result stood which I think is correct but should I have explained 2H as both majors or transfer. Behind screens if I didn't realize I made mistake I would have explained as transfer and since partners explanation woke me up I can't assume that I would have woken up.
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