Heat the red wine in a very large saucepan, add the mulled fix bags and let stand for 30 minutes, then remove.
Add the cherry juice and the preserving sugar. Bring to the boil, stirring constantly, and let simmer for a further 1 - 2 minutes, stirring constantly. Remove from heat and immediately fill into screw-top jars, close and let cool. Keep cool in the cellar until consumption.