They may have been editing the working hubs at this time to made the design stronger on the throat and bust areas at that time.1951 cents show the hair enhanced on some dies, others not showing this.
Even some proof dies had alterations on them:
1953 Proof Cent.
Through the years they battled with a weakening master hub and die ways of trying to see engraving to strengthen design areas. On was called Channeling:
Other issues with master hub doubling was seen on other years for many years:
Some years had some that were on some dies and other dies would be normal, Thus I think they were altering some working hubs.
So some dies were affected, some where normal. While there is no premium for these, it is just something to note about the coinage, to know what caused these issue. Finally in 1969, they re-created a new, Master hub. Because of the swelling of the die, the devices moving into the rim area:
Note the size of the bust and the enlargement of the devices and even the locations were different. In 1982 they had to do this with the cents again:
Because this had/was an issue then, they changed during the year. Thus the small and Large dates that year.
This not only happened on cents, on the Quarter dies, the master hub was recreated in 1983:
Again note the bust and the devices were enlarging and moving towards the rim. But because they waited until 1983, they avoided the large and small date issue. Sometimes know why answers other questions we have in our minds. CoopHome
: 1969 and 1982 cents had changes those years and Quarters on the 1983 coins. Why?
Swollen die issues. (Possibly 1974 cents could also be counted?)