Upvote:2
I, too, found CrossCountry's website and FAQs equivocal, so I asked CrossCountry about this in June 2019, and they told me that there is a charge if you are amending a specified train with a different operator.
So, it seems that the "no admin fee" rule applies only if the reserved train is a CrossCountry train and the amendment is made via the website (i.e.: not by telephone). Presumably, there would also be "no admin fee" for amending a journey involving multiple operators where the specified train is CrossCountry and the other operator(s) is/are merely for unspecified connecting trains. However, I do not have experience in amending a CrossCountry booking, so I do not know for sure.
Upvote:3
From a little research, I cannot find any stipulation restricting the offer to CrossCountry's own tickets. It does indeed sound like any non-(mobile/print at home) ticket priced by any operator bought through the CrossCountry website is subject to these waived fees, if amended within the time limit given. It's certainly surprising if true, and it's worth pointing out that I have not found positive confirmation of this; perhaps later I'll buy some advances I needed anyway and then see if it'll let me amend them.
Sources I found besides yours:
https://www.crosscountrytrains.co.uk/media/1454/customerreport16102016.pdf
https://www.crosscountrytrains.co.uk/customer-service/no-admin-fee