What is the max TBW rating for the SM841N?

I have a Samsung SM841N mSATA SSD I got in a pile of parts, and while it works it has 20.61 TB written so far to it. This is rather high for an SSD, but for a older SSD it’s probably not too unusual.

However, I need to know the max TBW before it “expires”, if you will so I can get an idea of how used it was before I got it. My application isn’t one where I can’t take chances since I just use it as a music SSD (although it only has 27GB left) and the files are on another drive I keep as a backup, so I do have them elsewhere.