data on max partition

Hello Experts,

we have a table defined as range partition by trans_dt, we have created partition up to Apr and we did not created rest of the partitions. now data is going to max partition.  i am looking for solution, insite , help to move data  from max partition to corresponding month partitions?

ie, need to move April data from max partition to April  partition.

what is the best way to do it. please advice.