[Moto G4 Plus Questions & Answers] echo92:
Yeah, retgb updates seem to be taking a little while to deploy... Like your experience, I was waiting for updates on the retgb channel too... Then I updated using the captured updates on XDA, which appeared to have worked okay :)

You've got 2 routes:

1) You can download the June 2017 OTA update from here to your device: https://drive.google.com/drive/folders/0B-GUyOfb8OgzR1VrQ1NHWDVmWE0

This is the same update that was on XDA, just mirrored to my Google Drive as the original link does not appear to work.

File name:Blur_Version.25.201.4.athene.retail.en.US.zip

Size: 56 MB

md5 checksum: 4ce250195b2eb71c960ec3b6579bc9d0

Ensure your device is fully updated to NPJS25.93-14-4 (bootloader should be version B1:05), you have a stock recovery, unmodified system and baseband (baseband version should end in .62R), as this update requires the March 2017 update. If your bootloader is still locked, this should all be applicable. Then:

Boot to stock recovery (notes on how to access stock recovery are here: https://xdaforums.com/showpost.php?p=72981796&postcount=58 )

Select 'apply update from SD card'

Locate the Blur_Version.25.201.4.athene.retail.en.US.zip on your device

Install update.

You may wish to wipe cache before rebooting.

Now, you should be updated to June 2017. There's also the September 2017 OTA (requiring the June 2017 patch) which you can apply in the same fashion: https://xdaforums.com/moto-g4-plus/how-to/captured-ota-september-security-patch-t3680367

I successfully flashed the June 2017 OTA onto my XT1642, retgb (so same as yours) that had previously been running on NPJS25.93-14-4 and have had no issues - my network provider, 3 UK, works well :)

2) If you want to, you can jump straight to the September 2017 stock build, which is running on my XT1642, and this is the method I chose to update (as I was rooted too, so needed a near clean start). I think it should be suitable for the Moto G4 too that you have, but you may wish to check the following stock ROM thread to confirm.

a) Download the September 2017 stock ROM (NPJS25.93-14-10): https://xdaforums.com/moto-g4-plus/how-to/stock-rom-npjs25-93-14-4-march-1-t3608138

b)Set up ADB as directed in the above post. Extract the ROM files in the same folder as your ADB terminal (so you should see files like oem.img and bootloader.img mixed with adb.exe and fastboot.exe)

c)If you wish to keep your data and do not need to re-lock your bootloader (i.e. your bootloader is already locked, or unlocked) and are simply updating, you could use the following fastboot commands to keep your data intact. Back up your data just in case your system becomes unstable and needs a factory reset, though I did not notice any corruption of my data. The initial boot was a little slow (presumably to rebuild caches and update links as necessary):

fastboot flash partition gpt.bin
fastboot flash bootloader bootloader.img
fastboot flash logo logo.bin
fastboot flash boot boot.img
fastboot flash recovery recovery.img
fastboot flash dsp adspso.bin
fastboot flash oem oem.img
fastboot flash system system.img_sparsechunk.0
fastboot flash system system.img_sparsechunk.1
fastboot flash system system.img_sparsechunk.2
fastboot flash system system.img_sparsechunk.3
fastboot flash system system.img_sparsechunk.4
fastboot flash system system.img_sparsechunk.5
fastboot flash system system.img_sparsechunk.6
fastboot flash system system.img_sparsechunk.7
fastboot flash modem NON-HLOS.bin
fastboot erase modemst1
fastboot erase modemst2
fastboot flash fsg fsg.mbn
fastboot erase cache
fastboot reboot

These commands should update your GPT, bootloader, recovery, system and modem to NPJS25.93-14-10, Sept 2017 patch. Though you could edit one of the flashing scripts - provided in the stock ROM thread - to match the above commands, I preferred to manually copy each command and execute the commands, checking each command flashed. As with anything affecting the firmware of your device, take your time in flashing. Using the September 2017 stock ROM, my XT1642 is still running happily with the September security patch (and seems smoother too :))

Bear in mind that with the June and September updates, the bootloader is updated to version B1:06. Thus, it makes downgrading risky. From the sounds of it, you're not interested in rooting/downgrading, so this might not be for you anyway. Just a heads up that downgrading from the June or September 2017 stock ROMs (e.g. by flashing the older stock ROM without flashing GPT/bootloader) and then accepting OTA updates may cause a device to hard brick. We have ways of attempting to rescue a device in this state but I really wouldn't like to try them if at all possible.

Good luck whichever route you choose :)