The 9 month window typically is when you will get a prime week started. For instance, Spring Break 2020 was bookable over the past two weeks at Valdoro and 2BR, 2BR+ and 3BR were all available if you grabbed three days and added a day as each became available (I did). But that isn't the only bite at the apple. Fixed weeks are automatically booked for owners (I had three units at Valdoro at one point). That means each owner must give up their week for it to become available to the rest of us. That doesn't always happen at 12-9 months out. Sometimes it happens 3 months out when an owner decides they want to do something else this year. I reserved a 2BR+ and a 3BR the past two years over Christmas week at Valdoro. I've had President's Day week at Sunrise. All booked August-October as fixed week owners give up their weeks. You won't login and find inventory is abundant like Orlando, you definitely have to check on it until something pops up, but it's no Lagoon Tower where it stays relatively blank for months on end.
I own a 3BR+ Platinum at 9,600 points. It cost me $12k to buy and has an MF slightly over $1k. The units I aim for are 2BR+ and 3BR at Valdoro. The plus just means a private grill and hot tub for your unit. The 3BR is nice because of the extra living room/dining space. Sunrise has larger units, but I haven't been in anything smaller than a 2BR there. We go less frequently to Utah because it requires a flight, but it has better availability than Valdoro.
My rationale for getting out of Valdoro and owning points with a low MF was based on having never used my fixed weeks. Ever. I didn't ski for 7 days straight and often I'd want to go for 4 or 5 days that crossed over a weekend. That eliminates the booking advantage. The 12 month booking advantage for a float ski week is for a Saturday to Saturday week in the unit size/season you own. A fixed week is already booked for you, so you have to proactively change it. Advantage gone if you want any change at all. Anyway, long story short, there are less expensive ways to maintain flexibility and enjoy the ski resorts than buying there.