So, if I understand the question, “Is there a difference between the following code snippets?”

Code:
MyByte VAR BYTE
MyByte = 155
Code:
MyByte VAR BYTE
MyCon CON 155
MyByte = MyCon
The answer is: No.

The only difference is how you read it as a human. For the PIC and it’s code, they are exactly the same.