I seem to recall that in the FoxCloud 2.0 app we used to be able to see the firmware version of individual battery modules (so that we can see if they are all consistent when adding a module). However I can't see this now - it only shows the serial numbers of the modules.
I also looked in the FoxCloud 2.0 website, and again, only serial numbers.
Fox have updated me to BMS 2.013 (from 2.001), KH7 manager (ARM) 1.67 (from 1.58), Master 1.71 (from 1.60), Slave 1.03 (from 1.02), W6 datalogger v1.12 (from 1.10), and I presume they also updated the modules in my stack after adding two EQ4300s, but I'm not sure how to check.
As expected, the nominal capacity goes up as if I had added 2x ECS4300-S modules, rather than adding the slightly larger capacity of the EQ4300s. Presumably to keep it balanced.