You won't be able to extend the expiry of tokens rather you will have to validate the token expiry and if it's expired generate new one programmatically using the adobe i/o library provided each time when making a call to adobe i/o.
You won't be able to extend the expiry of tokens rather you will have to validate the token expiry and if it's expired generate new one programmatically using the adobe i/o library provided each time when making a call to adobe i/o.