Newly detected backward compatibility error - TransportContract

Hi folks,

It turns out our decision to accept new dictionary entry names for
old constructs was hiding a backwards compatibility
problem.  Thankfully the sample instances revealed the need to update
the model checking.  And thankfully that updated model checking found
only the one problem revealed by the sample instances and not any
other problems of the same ilk.

Far below is the latest complete report and excerpted here below is
the new addition:

ASBIEs found in error: 1
Old Parent DEN: "Consignment. Details"
New Parent DEN: "Consignment. Details"
Old name: "TransportContract"
New name: "TransportContract"
Old DEN: "Consignment. Transport_ Contract. Contract"
New DEN: "Consignment. Transport Contract"
Old associated class: "Contract"
New associated class: "Transport Contract"

Old order:

1 ID

*2 IssueDate

*3 IssueTime

*4 ContractTypeCode

*5 ContractType

*6 ValidityPeriod

*7 ContractDocumentReference

New order (not including newly-introduced optional constructs):

New order (all constructs):

1 Contract

*2 NominationPeriod

*3 ContractualDelivery

What this means is that until this is fixed UBL 2.1 is not backward
compatible to UBL 2.0 because UBL 2.0 is expecting: