```bash
#!/bin/bash
#
# Description : This script takes a single file that lists loadable sources on s3 and exports
#               the compiled text files to the directory in which it is invoked, preserving
#               the scope/user_id/imei directory structure
#
# WARNING     : DO NOT USE FOR LARGE EXPORTS (ALTHOUGH YOU MAY WISH TO PARALLELISE LARGE EXPORTS
#               USING THIS SCRIPT, I.E. SPLIT THE FILE LISTING LOADABLE SOURCES INTO MULTIPLE
#               SMALLER FILES)
set -e
set -o pipefail

usage()
{
    echo "usage: aws-export.sh [ -f LOADABLE_SOURCE_FILE ] [ -o OUTPUT_DIR ]"
}
while getopts f:o: option
do
    case $option in
	f)
	    LOADABLE_SRC=${OPTARG};;
	o)
	    OUTPUT_DIR=${OPTARG};;
    esac
done

if [ -z "$LOADABLE_SRC" ]; then
    echo "########################################"
    echo "Exporting compiled text files from AWS"
    echo "########################################"
    echo "Date : $(date)"
    echo "Host : $(hostname)"
    echo "########################################"
    echo ""
    echo ""
    echo "You have not specified a file that lists compiled text with the '-f' flag."
    echo "Please enter the path to such a file : "
    read -r LOADABLE_SRC
fi

if [ -z "$OUTPUT_DIR" ]; then
    OUTPUT_DIR='./'
    echo "########################################"
    echo "Exporting files to current directory"
    echo "########################################"
fi


# Set timer to zero
SECONDS=0

while read -r COMPILED_TXT; do
    echo "Copying file $COMPILED_TXT"
    SUB_DIR=$(echo "$COMPILED_TXT" | awk '{split($0, path, "/"); print path[4]"/"path[5]"/"path[6]"/"}')
    echo "Target is : $OUTPUT_DIR/$SUB_DIR"
    aws s3 cp "$COMPILED_TXT" "$OUTPUT_DIR/$SUB_DIR" 2>/dev/null ; \
    echo "########################################"
done < "$LOADABLE_SRC"

DURATION=$SECONDS
echo ""
echo ""
echo "Export took       : $DURATION seconds"
echo "Files exported to : $OUTPUT_DIR"
echo "########################################"
```