Auto-expanding and Exchange Online Archiving

Please refer to KB article below to enable auto-expanding via Powershell. Initially they get 100gig of archive.

Its best practice to enable this from the start.

https://support.office.com/en-us/article/Overview-of-unlimited-archiving-in-Office-365-37cdbb02-a24a-4093-8bdb-2a7f0b3a19ee?ui=en-US&rs=en-US&ad=US

Enabling steps: https://support.office.com/en-us/article/Enable-unlimited-archiving-in-Office-365-e2a789f2-9962-4960-9fd4-a00aa063559e