Trees first, then the shingles
A River Ridge leak often starts in a valley that stayed wet under leaves, not in a bald field of shingles. We clean enough of the valley to see whether the metal and the underlayment are gone. A crushed deck under a fallen limb is a patch before any new shingles mean anything.
The houses are not Old Metairie mansions and they are not Kenner lake camps. They are shaded suburban roofs. Shade grows algae on asphalt. Algae is a surface stain. It is not, by itself, a reason to replace the roof.
