Is it a Guarantee room within a specific category or an IGT/OGT/VGT rate?
A guaranteed rate within a category becomes available when most rooms in that category have been sold and guarantees a cabin at that category or better. It has the same booking conditions, and close to the same cost, as booking a specific cabin. It's possible it costs a little more than the current price of some other cabins in the category because it has the possibility of getting something better.
A IGT/OGT/VGT restricted rate guarantees an Inside, Oceanview, or Veranda room or better. It requires full payment at time of booking with no changes or refunds allowed.
To return to the original question, it is possible that restricted rates will be available for cruises in January-March. Since final payment is typically due 2 months or so before sailing, having to pay at time of booking wouldn't be much of an issue. As mentioned, with a *GT rate you can't pick a specific room. You may also find that many onboard activities and excursions are sold out. If you don't care about the room and don't care about activities, you could certainly wait until you're recovered and look to see which cruises are still available and which, if any, have discounted restricted rates.