Correct me if I'm wrong but wasn't the reason for Hartlepool gaining ADL E200s for the 1 instead of more MAN E200s was due to timekeeping/reliability issues of the MAN E200s on that route? 
Just whenever I'm in Hartlepool there is several MAN E200s allocated to the 1 with the ADL's allocated to the town services. There was 5 on there today!