Photography Plan - Upgrading and Downgrading

I am currenlty using the Lightroom Plan with includes the new LR and 1TB of cloud storage ($9.99/mo). I'm thinking about upgrading to the Photography plan that includes the new LR, LR Classic and Photoshop but downgrading the cloud storage to 20GB ($9.99/mo). I am currently using 331GB of the cloud storage. 

How would I go about migrating from the 1TB plan to the 20GB cloud storage? Is it as "simple" as downloading and storing locally all the "Orignals and Settings" and then adding them to LR Classic? Will LR classic link the RAW files and the setting or do I lose all of the editing I've done?

Any help advice is appreciated.

Thanks..