For those of us with newer MT props, MT released SB 30 r4 a couple months ago. Applies to a small number of MTV 12 props & blades built or overhauled in 2013-2014 & requires replacing blade lag screws.
Here’s the whole list of MT service bulletins:
https://www.mt-propeller.com/en/entw/serviced.htm
The actual Service Bulletin mentioned above
https://www.mt-propeller.com/pdf/sbs/sb30r4.pdf