Textron Aviation has released a new communique ME-TP-012 for March 2019. The full communique can be viewed here (you’ll need to have a Textron customer account, free signup).
Chapters:
00: Form 337 for Equipment or STCs Installed at the Factory
52: Cabin Door Frame Corner and Striker Plate Filler
57: Wing Bolt Kits, Rev 1
57: Wing Tip Lenses for the King Air C90GTx and 250