Query on Birth registration

Looking at entries in the GRO indexes, can anyone tell me what 'Occasional Copy: A ' indicates after a birth registration?
It has happened with twins Hugh and Reginald Alston born in 1877. Is the fact they were twins something to do with this? (except it hasn't happened on any other twins in my family)
Both of these boys died in 1884, I presume from illness, as I haven't ordered a death certificate for either yet.

 

I can only see it against Reginald's name. a Google search for Occasional Copy A brings attention to Lost Cousins newsletter of December 2016. You could try looking at that.

 

There is an article in the LostCousins newsletter (09 Dec 2016) which you might find helpful:

- Ron -

 

Thank you for the link to LostCousins. So it looks like something was changed on Reginalds's first entry but not sure what. As these two twins died so young, I think I will leave buying the certificates until I win the lottery!

 

I found this entry on the FindMyPast site:

Monica RICHARDSON 1925 Q4 Newcastle upon Tyne vol 10B SEE D'30 MMN Towns

then in 1930:

Monica RICHARDSON 1930 Q4 Newcastle upon Tyne vol 10B page 162 MMN Towns

The first entry does not appear on the new index unless I have missed it (always possible) although the second does but with no MMN.

What does the SEE D'30 mean - I can guess but don't know for certain.

Was there an error on the first registration and the birth re-registered or is there another reason? Anyone any ideas - unless I buy the certificates of course!

 

Basically, the original 1925 registration was a different name - Monica Towns. The birth was then re-registered 4 years after the mother, Elizabeth, married Charles Richardson.

 

Thanks! I had missed that her parents didn't marry until just after the birth The birth wasn't reregistered until 4 years after her parents married.