I am new here. I have a question about a discontinued shingle brand I have never heard of, if is a 3 tab shingle. The homeowner swears it was called a “armstrong” shingle and was a 30 yr at the time. I removed one as a sample and it has no lettering on the back of it.
Reason I am asking is because it is an insurance job and if I can prove it is discontinued I can get the whole roof vs the front slope only.
Thanks in advance,