not having experience with your batteries but i will say that with my DIY packs of which 2 packs are brand new Winstons that are well balanced will drift on which one gives up more kWh's each day. they vary as much as 15% from each other and the third bank which is an older CALBS pack that are about 5 years old (bought used) can vary another 5% up or down compared to the other two packs.
many of the premade packs cannot balance between packs, (without additional comms cable's. My BMS's do not balance between packs unless I was to buy a special controller of some sort between each pack, however their cell level balance is fine.