Kitty Chaos?

I was happily in the land of nod, when I was woken at 0200 this morning with Sassy (cat) leaping off the bed, shouting with lots of yowls! I sat up, said to hubby 'I'm putting the light on' and looked round and there was Tango at the top of the stairs, looking at me?
We sleep on the 2nd floor.
He shot off.
I knew something wasn't right, so got up and came down to the kitchen to hear the catflap going and Tango sound asleep on the kitchen chair.???? So who was the Tango lookalike wandering round my bedroom at 2am in the morning!
I went and put the outside light on and there was Tango2, under the table on the patio. Oh he is beautiful!
I have been aware there has been a 'new cat on the block' I could 'smell' him and our cats have been exceptionally jumpy for a little while now!
So we have a new feral cat, son of the one we trapped and got 'done' at least 2 years ago.
Obviously didn't get him done early enough!
He is bolder, braver and eats for England, as all out bowls have been wiped clean recently and oh so beautiful! This puts us in a difficult position???????