Please remember that the clocks go back 1 hour this Sunday at 2am. As such, all salaah times will be one hour earlier as well. Check the timetable to make sure that you pray your salaah at the correct time.
Also note that during the winter months, Jumma salaah times are as follows:
1st at 12:25
2nd at 12:50
3rd at 13:15
Where possible it is best to arrive for the 1st or 2nd Jumma salaah as the 3rd one gets full quickly and you may end up missing the prayer altogether!