URGENT! Account access terming! How to offload/archive data for access outside of Smartsheet

I urgently need your help! My employer recently sold my division and I just found out that we will be removed from the original enterprise account as of March 1st. I've built a complex toolkit based on the PMO Office template and use Control Center and Dynamic View add-ons. This toolkit contains data that is subject to Federal regulations and must be retained for at least 10 years.

Has anyone had to deal with decommissioning a Smartsheet solution and/or creating a full backup or archive outside of Smartsheet?? I currently have 57 projects, each with a minimum of 3 sheets containing "source" data. Portfolio level content includes an Intake Sheet, portfolio rollup summary, multiple reports and a variety of data sheets used to compile metrics, etc. My workspace includes many more objects than this, but I'm just looking to capture the important data at this point. I wish I had time to somehow capture the structure, templates, etc., but that's a luxury I won't likely have time for.

I know the answer is out there somewhere, but I'm in a serious time crunch and hoping someone can help give me a jump start with this process. I sincerely appreciate any suggestions or insight anyone has to share. Thank you!!

UPDATE: For clarification, the content I need to preserve transitioned with my division, so we still own the data. The problem is that it currently lives within Smartsheet and was configured under the original enterprise account. We found out today that the transition period allotted for our Smartsheet account will end on 3/1, and our licenses with be revoked. The company that acquired my division is not transitioning use of the Smartsheet platform. I realize that I can export individual sheets to Excel, but hoping there might be a more efficient, and maybe more comprehensive, approach. I'm also looking for any insights related to transferring ownership or sharing workspaces with myself under free user account tied to my new email address.