This is a foolproof way to ripen tomatoes, which I have used for many years and hopefully it will work as well for you.
There is a perception that tomatoes can be difficult to ripen once the main summer is past. Often in October, as the nights are drawing in, the light levels are dropping, the plant is slowing down, and the fruit doesn't seem to ripen. The tomato plants still have loads of green tomatoes and chutney isn't the solution.
When it's turning chilly and you feel the best of the summer and early autumn sun has passed, cut the tomatoes off the plant on the vine and lay them on cardboard/newspaper in a spare room, conservatory or in a dish on a sunny windowsill and they will ripen. The Sunday Gardener has used this simple method to ripen tomatoes for several years without fail. The vines need to be somewhere warm, and the fruit will ripen.
I found this method to work well when one year moving house in early autumn. It was not practical to move the tomato plants and take them to the new house, and so the only thing to be done was to cut all tomato plants down. The trusses of fruit were cut and left on cardboard in a warm place, and 80%+ ripened.