The problems I see from the photos are;
- slot alignment in pic 2, installation was done by amateur
- humps and bumps in pic 1, decking is loose at best possible that the decking is delaminating or warping, very likely it would need replaced.
- questionable ventilation of the attic space, how many turbines in roof, what’s the cfm for the units, whats the attic space, is the air flow blocked by the hvac, what is the air intake source and does it have an adequate amount of NFAV
When doing a re-roof or tear-off (call it what you want) I always recommended that the deck be completely re-nailed, in my basic system this was an upsell on the better and best system it was included in the package…it is just that important. The process of tearing off the shingles involves and upward pull on the decking, this can and will loosen it, dependant upon the initial install quality of the decking the extent of the loosening of the deck varies. If the decking is not tightened down the result is often what you see in pic 2. Remember that often there is a change in the attic ventilation system done when a new roof is put on, this can cause changes in the average moisture control and heat control of the roof system below the shingles and this is what you get.
Recommend …examination by pro…due to findings…