So you're saying that, having made a mistake, they should not give the upgrade to the EXP who actually deserves it because the poor schmuck will never know why he didn't get the upgrade? I'm sure it happens, but that's not the way I'd want a business run.
Yes. The EXP was never promised the upgrade, whereas the OP was. Taking away something you have confirmed is a worse business practice than failing to give something that was offered conditionally.
Technically speaking, if the OP was confirmed in J and then downgraded involuntarily to Y, isn't there minimum compensation owed to him, either by the IDB law or terms of the COC?