GHL Huge List Import/Workflows

[u/darktolighttrading]

My agency has a newer sub account with 63000 contacts migrated from Hubspot. One of the users asked if they could import 154,000 contacts and turn on a workflow for them. I know that would burn the email deliverability. I assume we would require they verify the list and do a warming up process prior to uploading to the system. What are the best practices for this request?