Thanks for your reply.
Indeed, the terms CC is referring to the century, together with the next YY it combines the year in total.
I've just tested the date given by you but I'm afraid it is not valid.
It seems that the year (CCYY) needs to have a minimum of 4 characters. Same for the other items, MM & DD
1111-11-11T11:11:11.1
Is valid.
This makes it hard to validate the receiving files from other parties. Because we validate each incoming file with the ISO XSD.
If the sender sends the file with a dateTime like
111111-11-11T11:11:11.1
Then our internal processing will go in Error.
We may not adjust the ISO XSD-scheme, but I think we need to adapt our internal processing to comply with these cases.