If you are going to conduct that test of evaluating forecast form 1 and only 1origin , I would SERIOUSLY suggest that you evaluate accuracies from multiple origins where the model developed for the history may change as you have add new observation to the history. One origin for each series is always just 1 sample.
Differencing is just 1 part of a model which could contain ARMA structure . level shifts , time trends , seasonal pulses while incorporating remedies for non-constant parameters and remedies for non-constant error variance.
Select your tools of choice and compare the ensemble accuracy from a number of origins for each tool. Your tools should always include a provision for detecting anomalies and provision for delivering ROBUST estimates of the model form/parameters including testing the assumptions of the model form. If the tool doesn't do that then discharge that tool.