Microsoft Gives Tenants Opt-Out for Exchange Online Plus Addressing

Microsoft intends to make the Exchange Online plus addressing feature available by default to all Microsoft 365 tenants after April 17, 2022. If you don’t want this to happen, you need to update the Exchange Online organization configuration to update the DisablePlusAddressInRecipients setting to True. After the opt-out 30-day period finishes, Microsoft will proceed with the deployment, so don’t say you weren’t warned!

https://office365itpros.com/2022/03/21/exchange-online-plus-addressing/