I found their git repo yesterday and concur that they're only a handful of changes off OpenWrt master
jeff@deb-devel:~/devel/x-wrt$ git log -1 --abbrev-commit $( git merge-base x-wrt/master openwrt/master )
commit 5e247f3ac1
Author: Zoltan HERPAI <wigyori@uid0.hu>
Date: Wed Mar 13 21:14:47 2019 +0100
jeff@deb-devel:~/devel/x-wrt$ git log --pretty=oneline --abbrev-commit x-wrt/master ^openwrt/master
69b9019adb (HEAD -> master, x-wrt/master, x-wrt/HEAD) ramips: HC5X61 fix led
e3bd3268ff ramips: hack mac setting
36768a2a62 ramips: add factory_debug@0x2d00000 for R6220
faff7110c7 revert: ramips: fix support for MX25L25635F flash
cb99b22562 ar71xx: add X AP1200 support
6027732c10 Update issue templates
22cb9a8812 add ARRIS SBR-AC1750/TR3300 Router support
321cd1a431 sunxi: do md5 checksum validation
c21bc50799 x86: do md5 checksum validation
2dc76feb77 fstools: compat with auto_usb_mount
05dfdb7ba0 kernel: refresh kconfig
7bb5d99aba kernel: x86_64: FUSION_SAS support
a87357b94e ramips: mt7620: fix flash layout and usb support
434af49c9e ar71xx: add Phicomm K2T support
b77788ae60 base-files: remove the trailing partition first
d22b9cedd2 firewall: make compat with natcap
b37e9c8469 base-files: switch ports status trigger ifupdown
a4e1873af0 ramips: sysupgrade compatable with breed
ca3c087b43 make sure data/config store to flash/disk
6ab04676bc fixup for m25p shutdown
fdb91ce820 ipq40xx: simplify the setting of mac address
e68f8a2993 ipq40xx: add support for ASUS RT-ACRH17/RT-AC82U/RT-AC42U
55beb0a614 ipq40xx: easy install for ASUS RT-AC58U/RT-ACRH13
27dbfce10d ipq40xx: add scripts for adjust cpu's choice of interrupts.
78b843b4bd ipq40xx: essedma: disable default vlan tagging
d17d13b373 ipq40xx: essedma ethernet driver optimization
a7c0e93f72 backport support for natcap with kernel 4.14
4d2d94ef5a add TP-LINK TL-WDX6501 v7 support
936fc976b6 wireless-regdb: custom fix txpower and dfs
108cb87c1c move wpad-basic depends to target.mk
45edc12ca5 fix arm override compiler flags
00492ce9d2 ipq806x: update patch 0002-dmaengine-Add-ADM-driver
9896744a62 ramips: mir3g: setup wan macaddr
23182151d8 base-files: define DISTRIB_CODENAME
1afde5d569 ramips: add Xiaomi Mi Router 3 support
f2e465be00 ramips: add mt7620-nand driver for NAND flash
adfc908778 add AC9531 support
64d7f8a08b musl: fix mmap pass wrong offset to kernel
38d7a9dd4c rename Phicomm devices TITLE
b66deabc09 Netgear R6220: fix flash layout
ae9958df97 fix sysctl stop processing when IO error happens
3dc7f0ff99 custom: ap152/ap147 add qca988x/qca9887 support
a8e79cd0ea custom: ramips: add Puppies/Nxc200p Device support
38f0fe8285 custom: auto set default user and password for samba
45c6c0d8db custom: default lan ip start from 192.168.15.x
b23b5961bc custom: update feeds.conf.default for x-wrt
4ef540cc65 x86: fix bios mkimage during efi image generation
f4d60a8df9 x86: Generate EFI grub images
13fd6c988e tools: add sgdisk host build
1eef0f4fbe tools: add libpopt host build