Late to this discussion, but just to be clear - as you draw attention to it above - the "Lot number" to which you refer is actually an internal Corsair "Product number" or "Part number". Hence the PN identifier next to it on the base of the board. CH-9127014-NA is the unique code for all Corsair K95 RGB Platinum (MX Speed) keyboards with North America keyboard layout (the "-NA" suffix means "North America"). It is also often known as a SKU (stock keeping unit).
Given you were looking for a like-for-like replacement I would have been surprised if the PN were different. There is nothing suspect about identical "lot numbers". I guess the behaviour might be endemic to all models of this keyboard with the version of CUE you're using or be specific to your rig (eg, the specific make of USB controller and/or its configuration). Alternative way to put this point - if the symptoms you describe were limited to specific manufacturing batch you wouldn't be able to tell it from the CH-9127014-NA which all North American K95 RGB Platinums should have.
I hope in any case that the problem gets resolved for you. I too am keen to discover what the latest CUE software (2.24.50 updating 2.24.35) fixes. I would definitely try downgrading to an earlier version of CUE: personally I am still back on 2.20.72 as the least buggy release that works for me for my K70 RGB (MX Red). If it ain't broke...
