XPS 13 9370 touchscreen won't stay disabled.

I've noticed that with the 1.6.3 BIOS update the touchscreen won't stay disabled. I have disabled it in the BIOS settings and occasionally touch the screen and find that it responds to touch. Possible related factors:

1. I'm running Debian Buster.
2. I have sleep mode set to 'deep', not s2idle.
3. It seems to happen after suspending.

The next time I see it happen, I'll check the status with cctk and also see if I can disable it with that command.

This is not a terrible problem but seems like something that should not be happening. I see a number of posts that report the touchscreen not working after suspend so perhaps some code to fix that is not checking the BIOS setting on resume.

Edit:

Ah... No. I just suspended and on resume the touchscreen is working. cctk reported it disabled. I enabled it (using cctk) and disabled it so it again reports disabled but it is still working.