Failing to see the difference

I miss the days when buying a single was an easy affair. Generally you looked at the tracks on the 12” to check if it had everything the 7” did. I always bought the 12” and then the 7” if it had a different mix or b-side.

With the release of ‘Together’ the Pet Shop Boys have confused me somewhat. Once I got my head around the myriad of mixes and formats both digital and physical I made my choices and paid my money. However, I am failing to understand the difference between the 3:30 Radio Mix of the title track and the 3:31 Ultimate mix. I consider myself to have quite good ears and especially for Pet Shop Boys tracks but I am left baffled as to the difference between these two uniquely labelled mixes.

Is there a difference? Does anyone know? Is it a typo? The web seems to give me no answers and nobody else seems to asking the question. Am I going mad or are my ears defunct?