Perhaps I am wrong, but the 955 and 965 seem to share the same internal guts. Except for the different screen and a larger housing for a slightly bigger battery to compensate for the screen change.
They both seem to have the same sensor. Less than a year between them so definitely not a full redesign, seems more likely a cost savings measure or supply chain problem with the screen for the 945.
When I saw it I got excited it might be a sensor upgrade or at least add the ECG found on the Venu 2 Plus form last year (sometimes the mic and speaker on the Venu 2 Plus would be nice to for a quick response without grabbing my phone especially if it worked over an LTE/5G model).
At least with no internal changes to the unit, it can run the same software as the 955, which is already deep into the bug fixes (which often take over a year to get stable), though as history has shown there will likely be something purely software that the 965 will have or get that the 955 won't.
I was surprised that with all of the battery times they list on the page (with the broken battery details link), not a single time for all day Ox and/or with always on screen. I know the 945 gets about 1/3rd its battery life with the always on Ox sensor enabled. Though even with it disabled it never comes close to advertised.
Anyone have thoughts or more info?