String comparison in a Bash script called from terminal or keyboard shortcut gives different output

I have two monitors and I am calling a bash script to move the current window to the monitor above. Below there is a sample of my code (I changed the variable names to be more descriptive).

The problem is in the last if-statement if [[ $currentWindowPosition == "above" ]]. When I call the script from terminal and my window in the the monitor above I get:

currentWindowPosition=above!
The window will stay on this monitor

but when I call it from a keyboard shortcut (and redirect the output to a file) I get:

currentWindowPosition=above!
The current monitor is on the bottom

How come? I also tried different versions of that test but without success. Thank you in advance.

yOfCurrentWindow=$(xwininfo -id $(xprop -root | awk '/_NET_ACTIVE_WINDOW\(WINDOW\)/{print $NF}') | grep "Absolute upper-left Y:" | cut -d: -f2)
yResolutionOfmonitor1=$(xrandr | awk '/ connected/ { print $3 }' | sed -n '1 p' | awk 'BEGIN{FS="x"} { print $2}' | awk 'BEGIN{FS="+"} {print $1}')

if [ $yOfCurrentWindow -lt $yResolutionOfmonitor1 ] 
then currentWindowPosition="above"
else currentWindowPosition="below"
fi

echo "currentWindowPosition=$currentWindowPosition!"

if [[ $currentWindowPosition == "above" ]] 
then echo "The window will stay on this monitor"
else echo "The current monitor is on the bottom"
fi