It appears so. It is definitely closed from 10/24-10/31. Typically a rehab lasts longer than a week (usually 1-2 months)
Also, both waterparks usually close for rehab each winter, just not at the same time. The rumor is that Typhoon Lagoon is going second because they are going to be doing more than just a normal rehab. They are actually constructing a new attraction. By doing Blizzard Beach first, they won't have to worry if they are a little off target on the amount of downtime they need at TL.