Thank you for replying - the ticket number did not change and it makes sense why they can’t upgrade an SQ ticket number. It’s just annoying that their systems still email you the bid option; accept it; charge the card, realise the error, downgrade again to economy etc and now issue a refund. You would think a simple few lines of coding could stop redemption bookings being allowed to make upgrade bids. For example, on an SQ redemption it would be greyed out to pay to upgrade or upgrade using miles etc - it doesn’t sound that technical to put in place.

I would have accepted the €6 fast track as a gesture of goodwill, like you said, I am not any different to where I was two days ago in terms of the original booking!