By definition, an array is replicated over a particular process dimension if the dimension appears in its process group but not its signature (ie, the array has no range distributed over the dimension concerned).
As a rule it is good practise for programmers to maintain the same values in all copies of an element of a replicated array. If all arrays input to the communication schedules meet this requirement, it is guaranteed that those output do. This is not an absolute requirement on arrays passed to schedules, and the sections on individual schedules discuss the effect of defaulting on this rule.