Update ADB verbiage.

Change-Id: If63e1acaad160fd6b694f21d4696fdee9a4d1210
diff --git a/_google/googlepixel3xl.markdown b/_google/googlepixel3xl.markdown
index 3d72d2a..ce5f34a 100644
--- a/_google/googlepixel3xl.markdown
+++ b/_google/googlepixel3xl.markdown
@@ -12,7 +12,7 @@
 {% include disclaimer.html %}
 
 {% include supportstatus.html %}
-MTP does not work at this time. ADB also does not currently work. You may need to use a USB-OTG cable and a USB thumb drive to transfer files. TWRP may take a little longer than usual to boot on this device.
+MTP does not work at this time. ADB only works on the flashed version of TWRP. Unfortunately it does not work on the fastboot version of TWRP. You may need to use a USB-OTG cable and a USB thumb drive to transfer files. TWRP may take a little longer than usual to boot on this device.
 
 {% include download.html %}