Is it possible to downgrade or upgrade my prepaid plan for the upcoming month?

Is it possible to downgrade or upgrade my prepaid plan for the upcoming month?

Yes, you have the flexibility to downgrade or upgrade your prepaid plan for the upcoming month. To do so, simply purchase another 30 days credit and choose the desired plan for that month. You are free to select any plan that suits your needs.

https://www.kimchimobile.com/product/prepaid-recharge-credit-skt-eye-mobile/