That, “US Navy has 46% of our sub force on deployment,” not just at sea, but on deployment, and it is a high number.
Could be one of those year end things where they are trying to meet deployment rates, or maybe, as Galhran wonders, something is about to happen.
If it is prepositioning for some sort of action, the two most likely reasons to have subs out there loaded for bear would be to make some surprise cruise missile strikes, or SEAL insertions to go after some some nasty on a personal level.
In either case, it’s odd, even if it’s just a statistical glitch.