Galaxy A53 has received second update in this month, but the changelog tells a different story. As per the changelog, Samsung has again dispatched November security patch with it. I doubt it, and I think it is typing error from the team, because firmware version has changed to current month. The new firmware version is A536EXXU7DWL2 and comes in 243MB size.
If you look carefully at the end of firmware ‘DWL2ā, then it is new code, and ‘Dā indicates for December month. With the same code, Galaxy A34 & Galaxy A54 received December patch in the country, so it is new firmware. Anyway, you should download new software on your Galaxy A53 smartphone.