Little questions: did people immediately assume he didn't actually reach India? Did Asia get temporarily remapped to be much larger?
Bigger questions: did Columbus' claimed circumference become dominant? If not, why not? If so, when and how did we return to the classical/modern one?
Side question: is it fair to say that there's more-or-less continuity between Eratosthenes' estimate and the modern figure, or was he lucky and we figured it out better later?
I made a lentghy post about Circumference values in use in times of Columbus a while back. If you are interested in the origin and continuity of the theories, I expand here.
In short, confusingly, there both was and wasn't a continuity between Eratosthenes figure and values in Columbus times. The value was known but two things happened: one, the original Eratosthenes estimate is actually incorrect for like 10-15%, depending on the length of stadia, and two, the change of measurment units through time and place erased any sort of certainty in the actual value. Simply, people in Columbus times didn't use stadia so Eratosthenes number expressed in stadia was unclear what it actually was in their units. Also other values popped up, some accurate as well, but again differences in units and lack of certainty in conversion lead to loss of knowledge of actual value
I also wrote answers on At what point did Europeans realize New World was not India? and How quickly did news of the discovery of the new world spread across the old world? both relevant for your other questions