Disclaimer: Perhaps you talked to different Microsoft support reps who have made this easier but my experience is that few Microsoft people know this is possible at the moment. Also I'm not strong with PowerShell so I'm sure there are
I have 130 Business Essentials users and wanted one user to get the 5TB since he does a lot of video work and was at 1TB. Last month or so I opened a ticket with Microsoft and they said that the 5TB increase that was applied only to E1 and higher licenses. Recently I talked to sales/customer service and was told similar information. Yesterday at 5:05 I was able to increase the storage to 5TB.
How to guide from Microsoft:
https://support.office.com/en-us/article/Set-your-OneDrive-for-Business-storage-quota-7448173d-a38c-...
You need SharePoint Online Management shell
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