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.Scott Francis supported this idea ·Scott Francis commented
it's not just a genius idea, it's a REQUIREMENT from the relevant RFCs (822, 2822, etc.)
Not supporting "+" in the user-part means an email handling software is in violation of the RFCs that specify the standards that must be adhered to.