I am trying to update the renderings (more than 12) programmatically. I have around 1000+ items and each item as multiple languages (8+). I have developed the tool to see which all items as renderings inherited by standard values (600+) and items where inheritance is broken(400+). Now I can change the renderings for 600+ items by just changing the standard values but can you suggest me the best way to change the remaining 400+ renderings?
Note: Renderings can also have personalization.I may have to retain the personalization and datasource and just change the renderings to a different one.