There seems to have been a dramatic improvement in performance on Northern Rail this week, according to trains.im (see graphic below). For the past five days, ppm has been as follows :
Sun 29/12/19 76.8%
Mon 30/12/19 78.5%
Tue 31/12/19 84.6%
Wed 01/01/19 89.3%
Thu 02/01/19 83.2%
As I write...