I am using the old unlimited 50 plan. Compared to the new plan, i think old plan is much better. I am calling my parents quite often and they are using umobile as well so i am saving quite a lot from that way. from the new plan, it's too troublesome.

Do we automatically change from unlimited 50 to the new plan ka? or can we keep usin the old plan and the new plan only affects new subsribers?