Should be given in days extension, that is when 30days end, it will add another 30days till 88days are all used. So the last plan extension should be 28days. There is no info whether top up can be done on temp no. though Google AI said can. Since I manage to port in by 16th Dec, I will top up only when port in is completed later.The free 88 days are in credits? Prefer credits. And can you port in and top up immediately?