As per your statement, if many localites still refer to this train as 1 mail, we shall retain the name.
@all:
This is the very purpose of the Other Names field - to reflect current local usages which may be unknown to the larger travelling public. Yes, it may be a historic name, but whether or not some of the local travelling...
more... public uses that name will be known only to those who frequent that train. Such information will be known only to the localites. Yes, maybe other trains were also historically known as 1/2 Mail, etc. and people stopped using that name, but as per his statement, this train is still being referred to as 1 Mail. We find such exceptions everywhere.
Therefore, as always, we shall defer to the opinion of the local RFs in these matters. This goes for all trains and stations. People who live in the area know best.
We shall rest the matter here.
Thanks.