If the IGP issues or receives an LSA/LSP containing a prefix SID sub-TLV for a node SID or a backup node SID with a SID value that is a duplicate of an existing SID or backup node SID, the resolution in the following table is followed.
If the prefix is duplicate, it is equal and no change is needed. Keep the old LSA/LSP.
If the prefix is not duplicate, still keep the old LSA/LSP.
If the prefix is duplicate, it is equal and no change is needed. Keep the old LSA/LSP.
If the prefix is not duplicate, pick a new prefix and use the new LSA/LSP.