Link to source:
https://www.flyingblue.us/en/news/new-benefit-models
While I'd hope for Platinum improvements too (Especially something regarding the new seat blocking mechanism); it would be a little odd to announce those separately? Absolutely a possibility but why would they not include those changes in the same update..
The only thing that we do know at this time is that everything announced in the linked article already applies to Platinum. So I would not estimate the chance of them not mentioning Platinum specifically at 0% simply because..nothing will change.