Update IOS XE
Install mode is the recommended mode for booting a switch. This is due to the fact that bundle mode requires more memory, is slower to boot, and auto-upgrade for example isn’t supported in bundle mode.
Bundle mode is the legacy way of booting a switch using a .bin file which is referenced directly in the boot system command.
Install mode on the other hand expands (extracts) the bin file to flash ahead of booting.