Overwriting Vice Appending to MAILDIR Files

Greetings,

How do I get procmail to overwrite files in my MAILDIR vice appending to them?

I've tried many things, most recently:

        :0
        * ^Subject.*O2
        * ^Subject.*usage
        | /sbin/cat > O2_usage.rpt

All without success.  In the above case I get a "File exists" message
and it writes  it to the mbox not O2_usage.rpt.

Thanks for any help anyone can provide,

John Kent

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