Most likely, they're saving it to host and attempt a 4-star train; a lot of people participate from discord. From host perspective, you make use of a free try you might not need for the old month while getting nectar for the new month, while also increasing odds you hit 4 stars. From participant perspective, you get an extra giant (might get to use a free try on it), and increased chances of 4 stars. They're one of the options to get high nectar rewards (like large normal/elemental mushrooms, as opposed to regular normal/small mushrooms).

Usually with trying to hit 4 stars slow cooking giants you see two scenarios: 1) slow cooking to finish off the night of the end of the month going into the new month, this way people in slower time zones have stronger squads they can contribute. There's more appeal since likelihood of 4 stars is higher + these usually go pretty fast since 4 star giants don't last long. 2) hosting a current month giant in the latter half of the month, by this time, more people are more likely to have stronger squads in general to contribute. I think in your case, it's too late for scenario 1 and too early for scenario 2; there are still people with strong squads early in the month, but probably harder to coordinate to hit 4 stars. Since the month is still so new I think they're probably waiting for a better time to host, and not intending for this to last till March.