Mountroot error 19

I have just installed FreeBSD 11.0-RELEASE on a 1TB Seagate portable disk and it stops with
mountroot: waiting for device /dev/da0p2...
(probe0:umass-sim0:0:0:0): INQUIRY. CDB: 12 00 00 00 24 00
(probe0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
(probe0:umass-sim0:0:0:0): Retrying command
Mounting from ufs:/dev/da0p2 failed with error 19.

I am unable to eneter anything at the mountroot> prompt

This is a UEFI boot. I'm presuming it is a timeout waiting for the USB disk. If so, is there any way to make the system wait a little longer or retry a few more times?
You can try to set "" in /boot/loader.conf or at the loader prompt to 10000 or 15000. The standard value is 5000.
The delay made no difference. However, I can boot the same disks using a different ThinkPad X220 without any problem.
Try increasing the delay. I had a similar problem, and had to use 7000 (7 seconds). Just keep bumping it, until you find the "sweet spot". :)