As of NetSuite 25.2, you can change the validity of a refresh token for the OAuth 2.0 authorization code grant flow.
This gives you more flexibility when you set up OAuth 2.0 for use with integrations. The new default validity of a refresh token is two days.
It previously was three hours. You can make other updates this value on the integration record associated with the integration.
You can also change the length of time after which the integration user must reauthenticate. Both of these values can be changed to anything between one hour and 720 hours (thirty days in hours).
The option to change these values only applies to public clients.