Lesson translations (2020) - help wanted

I would like to add Spanish subtitles to Lesson 4. Working on the previous lessons, I found extremely helpful to use the English close-captions as the official reference (not the Auto-translated, but the “official” captions).
According to the Official P1-2020 thread the English transcriptions for this lesson is done. Are there any procedure to load or convert them into subtitles? Do you suggest an alternative workflow?
Let me know if help is needed for this.
Thanks!