IMO you could probably still get a cabin in February. Of course, it only takes one night's deposit which is fully refundable as long as you cancel at least 7 days before arrival (IIRC). I think because the weather is so nice that time of year (spring) that there is more action on getting a campsite especially over a weekend (some folks just come in for Friday-Sunday).
If you book the cabin as part of a package (with tickets, dining, etc) there are different cancellation rules so be aware of what your cancellation opportunities might be. But for a room-only ressie, it's one night deposit which you can always push out or get refunded.
Bama Ed