Hi,
I know you folks have acknowledged and are working on the PS4 issue where the frame rates will suddenly drop to a noticeable stutter after the 1.07 update but I thought I should let you know about a workaround I found that helps mitigate it. Perhaps this will help in the identification of the root cause and potential fix.
I noticed most frame rate drop occur after accessing your inventory, the inventory of containers (e.g. dead bodies, vehicles, barrels, etc.) and (I believe) sometimes when viewing loot in the game world. However, if you push the R1 button (item wheel) when experiencing a drop, this will return the frame rate back to normal.
I also noticed you can tap the R1 button after accessing your inventory for instance and this seems to reven a frame rate event from occurring. I have been using this workaround consistently and although it's annoying to have to do this, it works and I'm hoping this is of use to you folks while we wait for a fix.