Joined: 23 Nov 2006 Posts: 19270 Location: Inside the Matrix
Yes, MOD will allow appending to the end of an existing file. If you have an abend, it may not be as simple as merely appending to the end of what was already in the file. This could leave you with more or less than the correct amount of data.
If you are going to restart from some point, you must ensure that everything is back in sync to the restart point.