We do split stays most of the time - with a minimum of 3 nights at each resort. For you, since you're considering smaller contracts, consider whether that's something worth the hassle. We have more than enough points to book 3+ nights at 11 months at each of our home resorts, so we'll string together, say a 10-day stay at BLT(5) and Riviera(5). At 7 mo on the start of our BLT stay, I'll look at what's available to modify for those 5 nights. Say we decide to switch to BCV. Then at 7 mo before the start of the Riviera leg, I see what's available to switch using the Riviera points. Maybe BCV is available in the same size unit - if I switch to that, I will call MS later and ask them to merge the reservation. (Sometimes they can't/won't but will still link them). Or maybe since we are going to BCV at the start of the trip, we'd rather go somewhere out of the EP/HS area later, maybe AKV, maybe CCV? Anyway - it's nice to have the option to do a split stay and this gives us a lot of options, and we can wait list a few different resorts, also! (e.g. one stay we waitlisted BWV standard and BW views).
Like @RoseGold with opposite UY, you have 2 bands where your UYs overlap and you can use a lot of points without having to worry about banking deadlines. For Feb/Aug UYs, those bands are August-September and February-March. We have definitely liked the flexibility to (now) travel any time of year and as long as we stay aware of which UY we are using to book, we've always been within our banking deadlines. And in 6+ years of multiple trips, we've only had to cancel 1-2x (other than COVID), thankfully.
