Yes. Once they're downloaded to your PC, the files can't be changed. The issue is that when the change takes place, any new downloads will be in a format that can't yet be converted to epub.

To review, the FAA administrator was forced out because of a business vendetta of Elon Musk’s, Trump froze the hiring of new ATCs despite staff shortages, Musk launched an underhanded attempt to hollow out the whole federal workforce, and then the first US airliner crashed in 16 years.