(IMPs, we are vulnerable)
We play the 4th suit bid (1S here) as reasonably constructive, say (7)8+ pts, 5+ cards. I was West, partner said that I should have bid 3C to show a good spade raise rather than 3S which should really be pre-emptive. (In case it's relevant, we play fit jumps, so chances are 1S denies a diamond fit.)
Being an unpassed hand, I was worried about distinguishing that from something like Ax KJxx AKJxx xx where I need to ask for a club stop for 3NT. (I can't really start with X on this hand because of the spade shortage.) Maybe it's possible to play the cue bid in this position as two-way, but my understanding was the UCB only applies when raising partner's overcall, not his advance. Any advice for us here?
Thanks,
ahydra