Oversight? Likely story.

I have recently learnt that the Council send out a certificate to councillors once they are not councillors no more. I thought this was a new thinking only to learn it has been going for a while now. I wondered why I did not get one last yr? I asked the Chief Executive of Wigan Council if it was because I was a challenging member of the Council or was it because me and the then Mayor did not get on? The Council has come back and said it was an oversight. Likely story.