You can read the ganfeng datasheets here:
SD2 11133202 30Ah Pouch pdf SA2 78158240 30Ah Pouch 84162227 42Ah Pouch pdf SB6 11165260 50Ah Pouch pdf A51 86Ah Prismatic pdf A09 100Ah Prismatic pdf A11 100Ah Prismatic pdf A13 206Ah Prismatic pdf A14 71173200 277Ah Prismatic pdf A51 71173204...
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I don't see a discharge curve but I'll show the EVE as a comparison, so the loss is the highest when the cells are new and as they age the loss happens less. So yeah I think 3.5Ah loss after 200 cycles is very reasonable.
If this was grade B I bet that loss would have been closer to 20AH or maybe even 30AH.
You are lucky to have SOK and current connected provide you with batteries state side, I can assure the forum is filled with horror stories from Alibaba scam batteries, go read about Taico and other baloney brands, dead batteries after just 5 cycles.
The other option would be to DIY your own.