FortiAnalyzer VM license

At my job, I have "inherented" Fortianalyzer VM running 7.0 with 5GB/day perpetual license. The support contract ended on 2020 and I would like to request three years forticare support license inorder to update it and have support because tbh, I am not familiar with FAZ.

My question is that will the license start from the day that the license was purchased or will the license start from the day that the old one ended.