Hello tdehan,
Thanks for reaching Microsoft Community. We understand how important this information for you.
In this case, please press Windows logo key + R and type "msinfo32" and Enter. If you see Surface Pro 1796 then that means the device is the 5th generation of Surface Pro and was released in 2017. But if you see Surface Pro 1807 then it was released later and has the LTE advanced.
If this answers your question, please let our Community know by marking this post as an answer. This helps others who may have the same concern as you.
Kind regards,
StevenK