Waveshare 2.8 A TFT LCD stopped working after a reflash of the OS image (Orange Pi Zero LTS)

I have a Waveshare 2.8 A TFT LCD (https://www.waveshare.com/wiki/2.8inch_RPi_LCD_(A)) and I used it with the orange pi zero LTS board using the instructions given here: 

I used Armbian_5.90_Orangepizero_Ubuntu_bionic_next_4.19.57.img as the OS, downloaded from the Armbian download page archives. It worked on the first try, and displayed the console on the LCD screen. I was able to log into the Orangepi Zero board from the serial port (ttyS0) connected to the PC, from ssh in Putty on the same PC, and also from the console shown in the LCD (tty1) using a keyboard attached directly to the orangepi zero.

I started following other tutorials to try and get a GUI desktop to display on the LCD which didn't work. I finally formatted the sdcard and reflashed the armbian image to start fresh.

However, now the LCD screen is not showing the console no matter what I do. The LCD displays a white screen on power on, which seems to be normal. Then while the serial terminal on PC (ttyS0) is showing the boot up messages, at the point where I would expect the LCD to start showing the boot up messages simultaneously, all I bet is a black screen. Something is definitely happening, as the screen turns from white at boot up to black, but it's not showing the console display anymore.

I know that when the serial terminal on the PC reaches the login screen, the console on the LCD should have reached the login screen as well. If I blindly type in the username and password for the board in the black LCD screen, from the PC serial terminal I can see that log in from the LCD console succeeded (shown below). What is all this indicating? How I can I troubleshoot why the LCD is showing me a black screen, when it had worked the first time?

After flashing the image I usually do apt-get update and apt-get upgrade, but I have tried this again and again, both with/without the update/upgrade, and it is not working.

$ uname -a:

Linux orangepizero 4.19.57-sunxi #5.90 SMP Fri Jul 5 17:58:43 CEST 2019 armv7l armv7l armv7l GNU/Linux
 

$ w:

orangepizero@orangepizero:~$ w
 10:33:23 up 13 min,  2 users,  load average: 0.00, 0.00, 0.00
USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU WHAT
orangepi tty1     -                10:33    8.00s  0.53s  0.29s -bash
orangepi ttyS0    -                10:20    1.00s  0.64s  0.04s w  

$ lsmod | grep fb
fb_ili9340             16384  0
fbtft_device           40960  0
fbtft                  28672  2 fbtft_device,fb_ili9340