(1) Yes, if you continue to pursue a doctoral degree after completing a master's degree, you can apply to the lending bank for an extension of the loan term and grace period with the consent of the original guarantor. The maximum extension is the same as the loan term (16 years) and grace period (5 years) for the doctoral degree.
(2) After applying for the extension, you can defer the repayment of the principal and extend it to the end of the doctoral loan grace period, and the loan maturity date can be extended to the same as the doctoral loan maturity date.