Short answer regarding this particular issue:
The reference to "BCE" rather than "BC" means that 1)the author accepts the birth of Christ as an important dividing line in the tracking of time,and 2)he does not accept the importance of Christ Himself and,thus,refuses to use the standard reference "Before Christ".
This is being done more and more frequently by western "progressives" who are aghast at the fact that anyone would utter the word "Christ" under any circumstances.
No it means the author accepts that system as currently understood by most westerners.
The author could have used any of several systems, such as 452 BBE, 2776 AM.