There isn't much chance of ripe fruit where you are from flowers only just blossoming, so you might as well uproot the two that haven't flowered. If we have a very warm mild autumn you might just get some fruit of a useable size but probably not red. However if you do get any you can pick it before the nights get really cold and try ripening it off in the house. Best way is to spread it out somewhere reasonable warm and put a ripe tomato with the green ones. The gas given off the ripe one will help the green ones to ripen.

It might encourage the plant a bit if you feed it with tomato fertiliser once a week.

Thanks for that advice, will try feeding them as you suggest.

Jonathan8