Defunkd

[sapper6]

I picked up the XL recently. Seller described it as bought at Wembley on 11 July 1986. I already own the same shirt in L, which I've had for a couple of years and believe is period, so I've shot the two together throughout.
Both are SupaTees neck tags, both have Made in Brazil care tags, both single stitch on sleeve and bottom hems. The front print measures the same width and the same cap height on both, so as far as I can tell it's the same screen.
Measurements, flat:
L — 21.5" pit to pit, 28" length from high point of shoulder
XL — 20.5" pit to pit, 28.5" length
Two things I can't account for. The XL's neck tag shows almost no yellowing or softening next to the L's- especially for an advertised 40 year old shirt. The XL's print also has very little crazing where the L's is cracked throughout. Seller says it was worn into the early 90s and then stored. Also the XL measures narrower than the L despite being the larger size.
Photos below. In the stacked shots the L is the upper shirt unless noted.
Would appreciate any read on whether the XL is period.

[jimmyj]

You are a-ok here!

[sapper6]

Many thanks Jimmy J!