includes a line for 1916 coin which does not exists. No Royal mint(no mint mark) coins were struck as the coimage was done by Heaton. Most likely a novice collector did not see the mint mark and added a line. Also we can probably lock the data as no new findings are likely.
Don't know if the name is correct but the coins look uniform and are issued in a similar time frame and the series field is also intended to group such issue lines not just commemoratives (better then grouping them in the see also field witch is not intended for groupings like this but for similar items you could mistake for each other).
It looks indeed more of a duplicate line considering that it has the same mintage. If we agree that's the case I will ask the master referees to delete the year line and move members to the right one. As for the series field, I followed the guidelines I don't see anything wrong with that.
1916 line (without the H mint mark) is definitely a duplicate, can be verified in Krause or Remick - British Commonwealth coins. The reason I did not try it myself is that few people put their coins there, so it may require some manipulation in order to avoid losing their collection references.
