Will sun and rain change the miss color on our shingles?

We had our whole roof replaced with IKO Architectural shingles last week because of larger than golf ball size hail in early June. We used a highly rated contractor that we've used a number of times in the past to replace shingles from wind damage and siding from another hail storm a few years back. Every time we were completely happy with them. They do excellent work, clean up after themselves and are very respectful of our home when working on it. Everyone we have dealt with this from this company we've dealt with has been very friendly and helpful.
I've been sick with Bronchitis the last week and hubby was out of town. Because of our trust, I didn't come out to check the roof until it was completed and found the discoloration you'll see if the photos below. I shared one in black and white because it shows it better.
I talked to the foreman, he said he'd call his boss. When I didn't hear back from his boss, they are usually very prompt. I sent him a text with photos. He got back to me shortly saying the foreman called one of the owners instead of him and he didn't hear about it until my photos. He apologized for no one calling me. He'd got info before he called and said the owner contacted the shingle company, they said that some of the shingles held more "oil" from processing and in depending on sun and rain, the oils would wear off and match the rest of the roof within 3 to 8 months. If for some reason it doesn't the manufacturer would pay to replace the whole roof again.
Not having any experience with this, I thought I'd check with the Pros here to see if this is true.
Though I trust our contractors, we've never used this brand of shingles before and I don't want to wait up to 8 months to find out if our roof will look nice again.
I'm hoping you can help me with this Bob.
Woodbridge Environmental Tiptophouse.com
q roofs shingles sun color damage info, home maintenance repairs, roofing
q roofs shingles sun color damage info, home maintenance repairs, roofing
  26 answers