It appears that the ex4300-48MP does not support requesting of system snapshots.
It looks like based on this KB that there is no manual snapshots needed (Recovering the Primary Partition on EX4300-48MP Switches
As a test, I tried to run the command that that link discusses (set system software add on-primary force-host) but it fails.
Can anyone can confirm these assumptions? I suspect that command only works when system boots on the recovery partition.
My plan is to simply set "set system auto-snapshot" as that command is valid.
All other commands related to 'snapshot' results in "cli command not supported on 48mp" or something like that.