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.
The announcement at Ignite has an associated EHLO blog post here that you can reference: https://techcommunity.microsoft.com/t5/Exchange-Team-Blog/Exchange-Transport-News-from-Microsoft-Ignite-2019/ba-p/993417
Merged suggestion description: "Email notification for password expiration would help! So many users do not see the little tiny quick popup window ever. They start their computer and open Outlook and walk away. This results in never seeing when my password will expire. Would like to have some type of option to have an email sent daily once you hit the 14 day window of needing to reset your password. Would be nice if we could customize it with a company logo also and have the options to change how many times to notify an end user. Maybe we only want one email to go out and some may want an email everyday."