It can be done but you need to rewrite it manually and put in the proper order. This is easiest if you have a date/timestamp field in the file to sort on. If not then you need to keep track of the sequence you want manually either in a hidden subfile field or an indexed work file.
Register Hereor login if you are already a member
If you are looking for data in the subfile to be in a sequence of newest to oldest, your data needs to be stored with a timestamp. Process the file based on the timestamp as the key in descending order.
When you add new data, you will need to reload the subfile.