How Long Does 400,000 Baht Need to Be in the Bank Before Applying for Marriage Visa Renewal?

When you go back for renewal for the marriage Visa with 400,000 in the bank, how long does it have to be in the bank? For example, my extension date ends March 11, 2021. Do i require 400,000 in the bank 60 days from the date I apply for the renewal or 60 days from the March 11 date? I ask this as i hear you should apply for the extension about 45 days before its expiration.