[Moto G4 Plus Questions & Answers] echo92:
If you're looking to update to NPJ25.93-14 via OTA, you'll need to unroot and flash a stock recovery (and stock logo.bin if you hid your bootloader warning), else the OTA will not install. Of course, this will remove root and TWRP until you've updated. Also, bear in mind after the update there's 2 more security patches (March and June 2017)

Before attempting anything though, ensure you've got a backup of your data (including a TWRP backup of your device as it is) and move them off your device until you're completed.

If you don't have access to a stock recovery/logo.bin, you could use a stock fastboot ROM to bring you up to date - this will remove root and TWRP however. The latest fastboot ROM we have is the March 2017 build: https://xdaforums.com/moto-g4-plus/how-to/stock-rom-npjs25-93-14-4-march-1-t3608138

If you wish to update with the fastboot ROM (so bringing you up to the March 2017 build), you may wish to use the following fastboot commands, which will replace your recovery and remove root, but should not affect your data (however as with anything that affects your system, ensure you have backups regardless)

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

This fastboot ROM will formally update your device completely to NPJS25.93-14-4 (March 2017), but using these commands you will not have locked your bootloader. You may wish to wait for the June security patch (since OTA updates require a stock recovery, stock kernel and stock system) or proceed to rooting.

If you wish to root on Nougat, follow either: https://xdaforums.com/moto-g4-plus/how-to/guide-root-moto-g4-plus-supersu-android-t3587918 or https://xdaforums.com/showpost.php?p=72496111&postcount=270 Please ensure that you flash a custom kernel before rooting on stock - Motorola - Nougat on Moto G4/Plus devices.

If you do not wish to fastboot a stock ROM, you could flash a TWRP flashable of the March build. This will not update your bootloader, or GPT partitions (so will not completely update your device to the March build), but is a nice shortcut. Again, this will remove root (but not TWRP) and so you will have to re-root as for Nougat. https://xdaforums.com/moto-g4-plus/how-to/fxz-flashable-stock-npjs25-93-14-4-t3623010 for the TWRP flashable. This will also require you to flash the modem TWRP flashable file (included in the thread) as your fingerprint sensor may not work properly otherwise.

If you don't wish to update, and just want to disable the notification, have a look here: https://xdaforums.com/moto-g4-plus/help/how-disable-notification-update-t3459587/post73005893