Yep I received the same email and reached out to them for clarification. They apologised as they realised it is VERY badly worded
Here's a summary of what it should say, shared by one of the team
"This is a follow up email to our chat earlier regarding your questions about the changes to our advanced plan.
As we discussed, will not be losing the storage space you are already using.
For customers utilizing 35TB or more of storage per license, you’ll be able to continue utilizing your current storage amount at the time you’re notified, plus an additional 5TB credit of pooled storage for one year at no additional charge to your existing plan.
Upon the 12th month mark your account will switch to the new policy, however, you can contact our Sales department to discuss your options that better fit your needs. Starting from November, you will also have the option to purchase storage space from the Admin Console as well."
So still not great news from a long term storage perspective, but we do have 12 months to find an alternative solution. Ultimately it's becoming very clear that the unlimited cloud storage bubble has officially burst. If both Google and DropBox are now backtracking then everyone else will follow. I'm afraid cloud storage is not going to be viable for most unless you have relatively deep pockets or a business that can justify the outlay.
I have also booked a call tomorrow evening with someone on their business team who will discuss options post 12 months. Hopefully I'll be able to get a clearer idea of pricing post November.
I'll report back here once I know more