

Help with shirt sizing!
Hello! After some years of looking at the amazing shirts from the SS24 collection, I'm finally ready to pull the trigger (even though the second hand market still has them rather expensive). The thing is that I've found them on multiple sizes and have no idea whether to go for a size S or a size M, or where to find the intended measurements. The most important measurement for these as far as I can tell is the shoulder to shoulder.
I looked at the ysl.com site for any clues and the only one I found was that the regular ysl T-shirts use and S-M-L-XL sizing but the measurements listed on the chart were only for chest and they seemed awfully small for what I'm used of S and M to mean (I normally wear S for a relaxed T-shirt but here they say that the M has a 90cm chest which would be already fitted for me), and I'm not sure if the regular t-shirt measurements would even apply to these shirts though. It really doesn't help that I'm new to SLP.
Has anyone got any idea?
Would appreciate any clues from moral support/encouragement, what general strategy to follow, or in a perfect world, if you have any of these two shirts and would be kind enough to share the measurements I'd be particularly thankful forever!