WaveShare display only works after being hot swapped

I have a HDMI WaveShare display which remains blank when the Raspberry Pi is booted with it connected (the backlight comes on momentarily so it's getting power via USB) but it works fine when I boot with another display (HDMI TV) and then hot swap while the Pi is booted. This leads me to believe it's a driver issue - such as the incorrect driver or something being used when the WaveShare display is connected - but I don't know for sure.

It has worked previously so I'm not sure what changed.

I've got a fresh install of Raspberry Pi OS and followed the WaveShare instructions adding the following to config.txt:

hdmi_force_hotplug=1 config_hdmi_boost=10hdmi_group=2 hdmi_mode=87 hdmi_cvt 1024 600 60 6 0 0 0dtoverlay=vc4-fkms-v3d

I'm struggling to debug any further so any help or tips about what I should check next would be appreciated.