gnu/linux bash: close command at date time

example.sh

#!/bin/bash
# echo $DISPLAY
export DISPLAY=:1.0
# echo $XAUTHORITY
export XAUTHORITY=/run/user/1000/gdm/Xauthority

COMMAND="ffplay https://server5.mediasector.es/listen/bizkaia-irratia-musika/radio.mp3"

TIME="16:07"
DATE=$(date +%Y-%m-%d)
DATE_TIME="${DATE} ${TIME}"

SECONDS_UNTIL=$(($(date -d "$DATE_TIME" +%s) - $(date +%s)))

timeout "${SECONDS_UNTIL}s" ${COMMAND}