My work email is gmail. I'm retiring and my gmail account will be instantly locked and closed the day I leave. They do not allow me to migrate my work gmail account to my personal gmail account so if I can't make a copy, I will lose thousands of emails that I would like to continue to have for reference. I want to have permanent access to all my work gmails (since 2001) in Thunderbird. On April 30, my gmail account will cease to exist. I'm too nervous to change the Thunderbird/Gmail settings to POP in case there are any issues. I don't want to lose tens of thousands of emails if I don't do it properly. How can I "load" all my gmails into a Thunderbird file(?) that I can use permanently offline without fear that any messages will disappear?