LEGRAND Raritan PX3TS User Manual page 497

Exception: A few products, such as SRC, are developed much later so they may
not support older firmware versions, such as 3.5.0, 3.4.0, and so on. Therefore,
it is suggested to AVOID downgrading your cascading chain unless instructed by
Raritan or Legrand Technical Support. For minimum firmware versions, see
Cascading Restrictions in the Cascading Guide on the
(http://www.raritan.com/support/).
Upgrade from 3.3.10 or post-3.3.10 to post-3.3.10:
There is no upgrade sequence limitation.
Firmware version 3.3.10 is compatible with later firmware versions so you
can upgrade all devices of the chain in a random order.
Important: Raritan does not guarantee that no upgrade sequence limitation
will be required for all future firmware versions. It is highly suggested to
check the latest revision of the Cascading Guide or your product's User
Guide/Online Help before performing the firmware upgrade. The other
alternative is to always stick to the same sequence as the above diagram.
Downgrade from 3.3.10 to pre-3.3.10:
There is no downgrade sequence limitation. However, firmware
downgrade in a cascading chain is NOT recommended. Consult Raritan (or
Legrand) Technical Support first if downgrade is needed.
Firmware versions earlier than 3.3.10 are compatible with any pre-3.3.10
version so you can downgrade or upgrade all devices of the chain in a
random order when all firmware versions in the chain are prior to version
3.3.10.
Note: It is suggested to always stick to the same sequence as the above
diagram though there is no firmware downgrade limitation.
Chapter 7: Using the Web Interface
Support page
477