There appears to be an "out" on this - since the xPILtypes.xsd is noted as being non-normative.
Per the documentation - its OK to change this. Users therefore can change the type from xs:time to xs:token with an enumeration list. etc as they desire.
Thanks, DW
QUOTE from XSD header:
NOTE: This is the schema that users can customise the enumeration lists to meet their
exchange requirements. The enumeration values provided are ONLY SAMPLES and
is not complete. It is upto the application to decide what the values should be. To achieve
interoperability between applications using this specification, it is recommended that an
SLA/agreement is in place as to what the enumeration values will be used in this file