Unsupported package(s): dnscrypt-proxy2

I'm getting this error since about >1 Week while trying to build via "Attended Sysupgrade":

{
"url": "https://sysupgrade.openwrt.org",
"revision": "r23722-64782497db",
"advanced_mode": "1",
"sha256_unsigned": "",
"branch": "SNAPSHOT",
"efi": null,
"profile": "linksys,wrt3200acm",
"target": "mvebu/cortexa9",
"version": "SNAPSHOT",
"packages": [
"adblock",
"avahi-dbus-daemon",
"banip",
"base-files",
"bridge",
"busybox",
"ca-bundle",
"ca-certificates",
"dnscrypt-proxy2",
"dnsmasq-full",
"dropbear",
"ethtool",
"firewall4",
"fstools",
"getdns",
"haveged",
"ipset",
"iputils-ping",
"iwinfo",
"kernel",
"kmod-btmrvl",
"kmod-gpio-button-hotplug",
"kmod-mwlwifi",
"kmod-nft-offload",
"libc",
"libustream-mbedtls",
"logd",
"luci",
"luci-app-adblock",
"luci-app-advanced-reboot",
"luci-app-attendedsysupgrade",
"luci-app-banip",
"luci-app-firewall",
"luci-app-sqm",
"luci-base",
"mtd",
"mwlwifi-firmware-88w8964",
"netifd",
"nftables-json",
"odhcp6c",
"odhcpd-ipv6only",
"opkg",
"ppp",
"ppp-mod-pppoe",
"procd",
"procd-seccomp",
"procd-ujail",
"sqm-scripts",
"sqm-scripts-extra",
"stubby",
"tcpdump",
"uboot-envtools",
"uci",
"uclient-fetch",
"urandom-seed",
"urngd",
"vim-full",
"wpad-basic-mbedtls"
],
"diff_packages": true,
"filesystem": "squashfs",
"client": "luci/git-23.223.40904-987ae1a"

Start by tracing how the ASU service processes the package list for the reported OpenWrt profile and how it produces the “Unsupported package(s)” error. Reproduce the request with revision r23722-64782497db and dnscrypt-proxy2; done means the package is handled correctly or the unsupported-package behavior is clarified.