See FAQ. Any leftover premium balance will be prorated into your families subscription.
https://support.lastpass.com/s/document-item?language=en_US&bundleId=lastpass&topicId=LastPass/FAQ_Premium_to_Families_Prorate.html
Thanks. I read that about the prorating previously. I was actually looking for the link. Sorry, I wasn't clear. Great news though, your page was perfect. It had the link to upgrade and I completed it. Thanks for the help!!