Below is what our roofing expert John Stout from
Go Roof Tune Up had to say in response to your question:
I think you are correct. From the photo that you submitted, it is very difficult to see clearly the shingles and metal edge.
A common problem with “Zero” overhang at a rake edge is water going under the shingles and entering the house. The photo shows the metal edge as not being tight to the shingles. Examine this area. I think the solution will be to replace or repair the metal edge.
Thank you for your question.
Regards,
Your Friends at AskARoofer