display_default_lcd=0 doesnt appear to be working in 4.5

[acidtech]

I just switched to 4.5 and Im using a DPI LCD display. It was my understanding that display_default_lcd=0 should make the RPi default to the HDMI output instead of the DPI LCD. CUrrently it doesnt matter what I set display_default_lcd to or remove it entirely. The DPI LCD always is the primary display. I can mirror to the HDMI using gertCloner so I know the HDMI works. However I want to be able to go the other way(HDMI->LCD) because the scaling wont be as noticable(640x480 -> 320x240 will look better than 320x240 -> 640x480).

I'm using a slightly modified dpi18 overlay(mode 6 instead of mode 5). I dont expect that would have any effect on whether the LCD is default display or not.

RPi 3B
2.5amp Samsung USB charger
Retropie 4.5
The new image you just released.
No USB devices
Replicate by setting up a DPI LCD display.

Here is my config.txt:

# For more options and information see
# http://rpf.io/configtxt
# Some settings may impact device functionality. See link above for details

# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1

# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
disable_overscan=1

# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16

# uncomment to force a console size. By default it will be display's size minus
# overscan.
framebuffer_width=640
framebuffer_height=480

# uncomment if hdmi display is not detected and composite is being output
hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=1
hdmi_mode=1

# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
hdmi_drive=2

# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=4

# uncomment for composite PAL
#sdtv_mode=2

disable_splash=1

avoid_safe_mode=1
avoid_warnings=2

#uncomment to overclock the arm. 700 MHz is the default.
#arm_freq=800

# Uncomment some or all of these to enable the optional hardware interfaces
#dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=spi=on

# Uncomment this to enable the lirc-rpi module
#dtoverlay=lirc-rpi

# Additional overlays and parameters are documented /boot/overlays/README

# Disable Ethernet LEDs
#dtparam=eth_led0=14
#dtparam=eth_led1=14

# Disable the PWR LED
dtparam=pwr_led_trigger=none
dtparam=pwr_led_activelow=off

# Disable the Activity LED
dtparam=act_led_trigger=none
dtparam=act_led_activelow=off

dtoverlay=pi3-disable-bt
#dtoverlay=pi3-disable-wifi

#dtoverlay=pwm-2chan,pin=18,func=2,pin2=19,func2=2
audio_pwm_mode=2

# Enable audio (loads snd_bcm2835)
dtparam=audio=on
gpu_mem_256=128
gpu_mem_512=256
gpu_mem_1024=256
overscan_scale=1

#3.5 tft screen
dtoverlay=dpi18_2
overscan_left=0
overscan_right=0
overscan_top=0
overscan_bottom=0

enable_dpi_lcd=1
display_default_lcd=0
dpi_group=2
dpi_mode=87

#320X240
dpi_output_format=0x070016
dpi_timings=320 1 20 4 30 240 1 20 2 3 0 0 0 60 60 6400000 1