Sorry for the noob question. TL DR is the title + how long will it take for the data to started getting corrupted?

Some back story: i'm "the media guy" for my workplace and I tend to keep all the RAW photos, videos, all the rest of it, on my own drives. Now that I'm moving to another branch office, I might not need the data to be accessed as frequently, so I'm planning to only put them in a 2 TB ext 2.5' HDD that has been serving as the on site backup for those files in the first place for about 2 years, and may not touch it for a long time. The main copies are in an equally large ext SSD, which I intend to delete after I have completely moved office. I do have an off site backup.