Downgrade considerations
When you downgrade to an earlier software version, all the existing LAG configurations will be lost.
NOTE
When you downgrade to a software version that does not support 256 LAGs, only the first 128 trunk groups are deployed and the remaining LAGs will remain in the undeployed state. This is applicable to Brocade ICX 7750, Brocade ICX 7450, and Brocade ICX 7250 devices only.