Hi,

The OPC Foundation added 2 new https://reference.opcfoundation.org/v104/Core/DataTypes/StructureType/ values in the 1.04.10 errata:
-StructureWithSubtypedValues 3
-UnionWithSubtypedValues 4

and swapped some PubSub-related configuration Structures to use the those. Other than those being visible in the addresspace Types part, that should be the only change (as we do not use them yet in anything). Are the clients failing just due to that, or something else?

Can also be our bug due to the changes, but I need more info.

As for the ‘revert’, not exactly (i.e. not supported yet, might be technically doable). We have never tried, but technically the base information NodeSet XML is inside the SDK jar; it is loaded during server initialization. Thus “downgrading” that might work, though the code around would assume the newer, but it might not be a problem. We might need to continue via email about this.

Also it should be noted that Codegen is also sort of locked to a particular base information model (as there is 2 of them, one has services info as addition stuff, that is embeded and the 2 must match, some improvements could be made in the future), plus the base information model outputs are edited by us in the XXXTypeNode classes (e.g. Method implementations).