We announced at Ignite that we are actively working on bringing dynamic plus aliases to Office 365.
To get around existing usage, the plan is for an opt-in setting. Our ETA is to have this available for all customers by the third quarter of 2020.
I will keep you updated in Uservoice on our progress.JIB supported this idea ·JIB commented
Still cannot believe Office 365 doesn't support RFC 5233 subaddressing. Outlook.com does it well. As does Gmail. This is a pretty widely used feature, so please make it happen Microsoft!