You are not alone friend.
I was able to flash the update once, but it didn't take and just powered off the phone every few minutes at random. Was completely unusable for me.
Note of caution, somehow in all the flashing of different things I managed to wipe/corrupt my EFS/Persist partitions, which has now led to major issues with 4G and Wifi on my device (shutting off and on every 30 seconds or so). Learn from my own idiocy and make sure to take a back up of the efs and persist partitions and save it OFF the device. Will save a lot of headaches in case something bad happens (as it did for me).
I also lost wifi, as on and off and then after reinstall attempt lost all connections mobile no sim no imie.
Wiped everything then flashed latest latest stock ROM fixed everything but hotspot, installed Aug RR, fixed hotspot.
---------- Post added at 02:05 AM ---------- Previous post was at 01:15 AM ----------
I'm sorry I just can't figure out, how to install the August Update.
The May Update no problems to install.
Every Time I use your method above I'm stuck in a Boot Loop.
Again my steps (correct me if something wrong)
TWRP: wipe (data,system,cache) - Format Data
TWRP: Install RR August
TWRP: Install DM
After that anything failes in a bootloop
If it won't boot then try format just data again after boot attempt. The OP also recommended doing it twice in the install instructions first post.
Is it showing the RR boot animation, or just going from the Moto logo to freeze?
My first boot took me to RR recovery with "can not load Android system" so I wiped/format data in RR recovery then it booted after about 3 minutes. OP states give up to ten minutes.
Also, are you just trying to install the update alone or decrypt so you can install TWRP?
And yes in fastboot TWRP:
wipe everything
format data
Aug RR
dm-verity (only if you want to decrypt and install TWRP after decrypt, has to be the jlb ramdisk from OP.)
Boot, if no; try to boot to RR recovery from bootloader and
Format data again, should boot.
Let me know. My XT-1927 coming from latest stock ROM (RELTA DS) reflash is working with Aug RR, and have TWRP and magisk.
I did have a problem with one slot so try alternate.
I will repeat it again if you can't get it.
---------- Post added at 02:16 AM ---------- Previous post was at 02:05 AM ----------
I'm sorry I just can't figure out, how to install the August Update.
The May Update no problems to install.
Every Time I use your method above I'm stuck in a Boot Loop.
Again my steps (correct me if something wrong)
TWRP: wipe (data,system,cache) - Format Data
TWRP: Install RR August
TWRP: Install DM
After that anything failes in a bootloop
See my last post I accidentally posted to Dave c who replied to yours