Currently, when default values of custom fields are mapped according to certain projects or issues types, then when those are changed, the default value does not change, and remains the original value.

An example :

1. Given 2 projects in JIRA, A and B
2. There is a 'Number' custom field
3. For this 'Number' custom field, if an issue is created in A, the default value would be '12345'. If it is created in B, the default value would be '2468'.
4. When a user creates an issue, he/she first chooses A (within the create issue form). The 'Number' field is understandably set to 12345 by default. However, if the user was to change the project to B instead, the value would not change to 2468, but remain with 12345

It would be much more convenient if the default values can keep track of any changes performed, so that the value would be updated automatically