Sequoia - migrating Keychain app Secure Notes to Notes app

For various reasons, I have approaching 1,000 Secure Notes in my Keychain. Quite a few are old, many get used once or twice a year, not all are website passwords. I'm reluctant to lose/delete any, just in case … Updating from Sonoma to Sequoia 15.2, I've discovered new Secure Notes cannot be added to Keychain and Apple recommended using locked notes in the Notes app. For existing Keychain Secure Notes, the Apple solution is a manual copy/paste to the Notes app and locking the individual notes. Except I have many 100s, approaching 1,000 - doing it one-by-one is going to take hours and inevitably result in some errors. I have discussed on the Apple support forums - no bulk migration solutions offered. I have directly chatted with an Apple Support advisor - copy/paste one-by-one is the "official" Apple solution. I did find a 3rd party tool on github (secure-note-exporter) but it's years old. Does anybody have any bulk migration solutions?