Using cli.py to set powerwall battery backup reserve returns 405?

[ryanseddon]

I'm trying to automate changing the battery backup reserve to force grid charging during cheap times and can successfully update the back reserve percentage via the python library using the following code:

import teslapy
with teslapy.Tesla('elon@tesla.com') as tesla:
    batteries = tesla.battery_list()
    batteries[0].get_battery_data()
    print(batteries[0])
    batteries[0].set_backup_reserve_percent(15)

But when trying to do it via the cli.py with the following command I get a 405 response?

python cli.py -e elon@tesla.com -a BATTERY_BACKUP_RESERVE -k backup_reserve_percent=15

Am I not correctly setting the key value or is it something else?