merging results of dynamic key lookup result in multiple objects instead of a single object

[RoadRunnr]

withyq 4.30.1 on Ubuntu 23.10

given this input:

{
    "otp": {
	"24.3":	{
	    "alpine": "3.16",
	    "rebar3": "3.20",
	    "version": "24.3.4.13",
	    "download_sha256": "111a00cf3fd512526e35f232fb18e6e95c7a9b1688bb38d7dd8152a82e0ea684"
	},
	"25.3":	{
	    "alpine": "3.17",
	    "rebar3": "3.20",
	    "version": "25.3.2.3",
	    "download_sha256": "8c1e8811201d1e9cc806b74393db16e89a119f412e16bb5f6181d54cd102eb4f"
	},
	"26.0":	{
	    "alpine": "3.18",
	    "rebar3": "3.22",
	    "version": "26.0.2",
	    "download_sha256": "47853ea9230643a0a31004433f07a71c1b92d6e0094534f629e3b75dbc62f193"
	},
	"26.1":	{
	    "alpine": "3.18",
	    "rebar3": "3.22.1",
	    "version": "26.1.1",
	    "download_sha256": "30de56e687cef15c73ef2e2e5bc8a94d28f959656e716e0a65092af7d360af57"
	}
    },
    "rebar3": {
	"3.20": {
	    "version": "3.20.0",
	    "download_sha256": "53ed7f294a8b8fb4d7d75988c69194943831c104d39832a1fa30307b1a8593de"
	},
	"3.22": {
	    "version": "3.22.0",
	    "download_sha256": "28b256038b445ec818d2cc33000b3217f42a946219ede55ab5970503bfcf6647"
	},
	"3.22.1": {
	    "version": "3.22.1",
	    "download_sha256": "2855b5784300865d2e43cb7a135cb2bba144cf15214c619065b918afc8cc6eb9"
	}
    }
}

And this yq expression:

otp=26.1 yq -o j '(.otp[env(otp)] | with_entries(.key |= "OTP_" + upcase)) * (.rebar3[.otp[strenv(otp)].rebar3] | with_entries(.key |= "REBAR3_" + upcase))' versions.json

I would expect to get this output:

{
  "OTP_ALPINE": "3.18",
  "OTP_REBAR3": "3.22.1",
  "OTP_VERSION": "26.1.1",
  "OTP_DOWNLOAD_SHA256": "30de56e687cef15c73ef2e2e5bc8a94d28f959656e716e0a65092af7d360af57",
  "REBAR3_VERSION": "3.22.1",
  "REBAR3_DOWNLOAD_SHA256": "2855b5784300865d2e43cb7a135cb2bba144cf15214c619065b918afc8cc6eb9"
}

The problem is, I get this:

{
  "OTP_ALPINE": "3.18",
  "OTP_REBAR3": "3.22.1",
  "OTP_VERSION": "26.1.1",
  "OTP_DOWNLOAD_SHA256": "30de56e687cef15c73ef2e2e5bc8a94d28f959656e716e0a65092af7d360af57",
  "REBAR3_VERSION": "3.20.0",
  "REBAR3_DOWNLOAD_SHA256": "53ed7f294a8b8fb4d7d75988c69194943831c104d39832a1fa30307b1a8593de"
}
{
  "OTP_ALPINE": "3.18",
  "OTP_REBAR3": "3.22.1",
  "OTP_VERSION": "26.1.1",
  "OTP_DOWNLOAD_SHA256": "30de56e687cef15c73ef2e2e5bc8a94d28f959656e716e0a65092af7d360af57",
  "REBAR3_VERSION": "3.22.0",
  "REBAR3_DOWNLOAD_SHA256": "28b256038b445ec818d2cc33000b3217f42a946219ede55ab5970503bfcf6647"
}
{
  "OTP_ALPINE": "3.18",
  "OTP_REBAR3": "3.22.1",
  "OTP_VERSION": "26.1.1",
  "OTP_DOWNLOAD_SHA256": "30de56e687cef15c73ef2e2e5bc8a94d28f959656e716e0a65092af7d360af57",
  "REBAR3_VERSION": "3.22.1",
  "REBAR3_DOWNLOAD_SHA256": "2855b5784300865d2e43cb7a135cb2bba144cf15214c619065b918afc8cc6eb9"
}

Using each of dynamic key lookups by itself works:

$ otp=26.1 yq -o j '(.otp[env(otp)] | with_entries(.key |= "OTP_" + upcase))' versions.json
{
  "OTP_ALPINE": "3.18",
  "OTP_REBAR3": "3.22.1",
  "OTP_VERSION": "26.1.1",
  "OTP_DOWNLOAD_SHA256": "30de56e687cef15c73ef2e2e5bc8a94d28f959656e716e0a65092af7d360af57"
}
$ otp=26.1 yq -o j '(.rebar3[.otp[strenv(otp)].rebar3] | with_entries(.key |= "REBAR3_" + upcase))' versions.json
{
  "REBAR3_VERSION": "3.22.1",
  "REBAR3_DOWNLOAD_SHA256": "2855b5784300865d2e43cb7a135cb2bba144cf15214c619065b918afc8cc6eb9"
}

But the moment I combine them with *, suddenly I get 3 objects. Is that a bug or am I doing something wrong???

Update: it does work if I omit the with_entries expressions. But I can't see why those should effect the outcome of the merge in any way. After all, they are in a different scope of the expression.