I'd put an adequate front apron in while you have access it doesn't extend past the tiles by 150.
Water will just run off the step/cover flashing into the roof space from what I can see mate.
That's the part im on about I normally extend past the chimney (not tiles my mistake) 150mm and weld the front apron.
It looks in line therefore anything that runs off the soakers, assuming there is any, will run behind the front apron.
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