Explanation
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/mds9000/sw/8_x/release_notes/epld/epld_rn_8x.htm Graphical user interface, text, application, email Description automatically generated

"On a Cisco Nexus 9500 platform switch that has two supervisor modules, upgrade the EPLDs for the standby supervisor and then switch the active supervisor to the standby mode to upgrade its EPLDs. The supervisor switchover is not disruptive to traffic on Cisco Nexus 9500 platform switches. On a switch that has only one supervisor module, you can upgrade the active supervisor, but this will disrupt its operations during the upgrade." Under Installation guidelines.
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/92x/epld-rn/ nxos_n9K_epldRN_924.html