I don't believe it is open first thing in the morning. I would guess it will depend on the weather how busy it will be in Feb. You may get soaked.
If you are travelling at a busy time in Feb (week before or after President's Day), or planning a weekend, you should check out SW Black Friday sales. Last year I got one day of Quick Queues for whopping $12.50/each, and just planned Infinity Falls on that day (it was mid-90s and the afternoon line was 90+ min - we rode 3x in about 40-45min and it was very refreshing)! Plus we were only wet the one day. Would have gone another day but didn't time it right to not have a 60+ min wait (on slow but hot weekdays).
You just have to have your days planned by Nov, because QQ is date specific and non-refundable.
That said, most of Feb is much cooler and less busy, so you should be able to do noon-ish or late afternoon with reasonable waits.