This is problematic. New msg IDs beyond this point in list will have 2 possible ID numbers. I think these need to be at the end of the normal message section of the list and given a very high ID number (e.g. 0x7000) so there is no chance of conflicting with other message IDs.
I can see that the override cmd function is named per the override message it sends (from f/w code), but the name doesn't seem to match what it does exactly. This is not an on/off or start/stop cmd. It is a set piston pump target flow rate command. Work with Vinay and consider renaming here and in f/w.