diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index b786d4a38..857a8e1c8 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -15,8 +15,8 @@ jobs:
 
     strategy:
       matrix:
-        otp_version: [23, 24, 26]
-        os: [ubuntu-20.04] # latest only runs >= 24.2
+        otp_version: [26, 27, 28]
+        os: [ubuntu-latest] # latest only runs >= 24.2
 
     container:
       image: erlang:${{ matrix.otp_version }}
diff --git a/.github/workflows/shelltest.yml b/.github/workflows/shelltest.yml
index 759460e9b..aaeeb6d16 100644
--- a/.github/workflows/shelltest.yml
+++ b/.github/workflows/shelltest.yml
@@ -17,7 +17,7 @@ jobs:
       matrix:
         # TODO: make a batch of tests that runs on nodetool rather
         #       than the new connectivity mechanism
-        otp_version: [25, 26]
+        otp_version: [26, 27, 28]
         os: [ubuntu-latest] # latest only runs >= 24.2
 
     steps:
diff --git a/.github/workflows/wintest.yml b/.github/workflows/wintest.yml
index dcc0259df..4451a2b3b 100644
--- a/.github/workflows/wintest.yml
+++ b/.github/workflows/wintest.yml
@@ -15,7 +15,7 @@ jobs:
 
     strategy:
       matrix:
-        otp_version: [24, 25, 26]
+        otp_version: [26, 27, 28]
         os: [windows-latest]
 
     steps:
diff --git a/priv/templates/extended_bin_windows_ps b/priv/templates/extended_bin_windows_ps
index 7f37dd8ca..8008bb95a 100644
--- a/priv/templates/extended_bin_windows_ps
+++ b/priv/templates/extended_bin_windows_ps
@@ -62,7 +62,8 @@ $service_name = "${rel_name}_${rel_vsn}"
 $nodetool = "$rootdir\bin\nodetool"
 
 $bindir = "$erts_dir\bin"
-$werl = "$bindir\werl.exe"
+# since OTP-26, werl.exe is just erl.exe, so link it directly
+$werl = "$bindir\erl.exe"
 $erl = "$bindir\erl.exe"
 $erlsrv = "$bindir\erlsrv.exe"
 $escript = "$bindir\escript.exe"
diff --git a/priv/templates/psutil b/priv/templates/psutil
index 5c54a6915..da172ed24 100644
--- a/priv/templates/psutil
+++ b/priv/templates/psutil
@@ -17,13 +17,13 @@ function Find-ERTS()
 
     # Get the ERTS dir from erl
     $erl = (Get-Command erl).source
-    $erl_root = & $erl -boot no_dot_erlang -noshell -eval 'io:format(\"~s\", [filename:nativename(code:root_dir())]), halt().'
+    $erl_root = & $erl -boot no_dot_erlang -noshell -eval 'io:format("~s", [filename:nativename(code:root_dir())]), halt().'
     if (Test-Path "$erl_root\erts-$Vsn") {
         return @($erl_root, "$erl_root\erts-$Vsn")
     }
 
     # Expected $vsn but not found, get ERTS version installed
-    $erts_vsn = & $erl -boot no_dot_erlang -noshell -eval 'io:format(\"~s\", [erlang:system_info(version)]), halt().'
+    $erts_vsn = & $erl -boot no_dot_erlang -noshell -eval 'io:format("~s", [erlang:system_info(version)]), halt().'
     if (!(Test-Path "$erl_root\erts-$erts_vsn")) {
         Write-Error "Can not run the release. There is no ERTS bundled with the release or found on the system."
         # Terminates here due to $ErrorActionPreference = "Stop"
@@ -172,4 +172,4 @@ function Get-Cookie()
     }
 
     return $cookie
-}
\ No newline at end of file
+}
diff --git a/shelltests/wintest.ps1 b/shelltests/wintest.ps1
index 82fd33c56..d0b2f317e 100644
--- a/shelltests/wintest.ps1
+++ b/shelltests/wintest.ps1
@@ -24,9 +24,12 @@ mkdir $rebar3_dir | Out-Null
 # Clone latest rebar3 and build with relx as a checkout
 Push-Location $rebar3_dir
 & git clone "https://github.com/erlang/rebar3" .
-mkdir _checkouts | Out-Null
-New-Item -ItemType SymbolicLink -Path "_checkouts\relx" -Target "$PSScriptRoot\..\..\relx" | Out-Null
-(Get-Content rebar.config) -replace 'relx(.*)build/default/lib/', 'relx$1checkouts' | Set-Content rebar.config -Encoding ASCII
+Remove-Item -Path "vendor\relx\src\*" -Recurse -Force
+Remove-Item -Path "vendor\relx\priv\*" -Recurse -Force
+Remove-Item -Path "vendor\relx\rebar*" -Force
+Copy-Item -Path "$PSScriptRoot\..\..\relx\src\*" -Destination "vendor\relx\src" -Recurse | Out-Null
+Copy-Item -Path "$PSScriptRoot\..\..\relx\priv\*" -Destination "vendor\relx\priv" -Recurse | Out-Null
+Copy-Item -Path "$PSScriptRoot\..\..\relx\rebar*" -Destination "vendor\relx" -Recurse #| Out-Null
 cmd /c bootstrap.bat
 Pop-Location
 ""
@@ -61,6 +64,9 @@ if ($LASTEXITCODE -ne 0) {
 }
 ""
 
+Get-Process | Out-String -Stream
+Get-Service -Name powershell_release_0.1.0 | Out-String -Stream
+
 "*** Start service"
 & ".\$release.ps1" start
 if ($LASTEXITCODE -ne 0) {
@@ -68,6 +74,9 @@ if ($LASTEXITCODE -ne 0) {
 }
 ""
 
+Get-Process | Out-String -Stream
+Get-Service -Name powershell_release_0.1.0 | Out-String -Stream
+
 "*** Ping service"
 & ".\$release.ps1" ping
 if ($LASTEXITCODE -ne 0) {
diff --git a/src/relx.erl b/src/relx.erl
index ab3ca332c..593c6bb9b 100644
--- a/src/relx.erl
+++ b/src/relx.erl
@@ -127,6 +127,10 @@ build_tar(RelName, Apps, State) when is_atom(RelName) ->
     build_tar_(RealizedRelease, State),
     {ok, RealizedRelease}.
 
+%% Ignore Dialyzer warnings on this, `no_warn_sasl` is a valid option
+%% but the `systools:make_relup/4` spec is outdated and this causes
+%% warning as late as OTP-28, and all calls in the chain fail analysis in turn.
+-dialyzer({nowarn_function, [build_relup/4]}).
 -spec build_relup(rlx_release:name(), rlx_release:vsn(), rlx_release:vsn(), rlx_config:t() | rlx_state:t())
                  -> {ok, rlx_state:t()} | {error, term()}.
 build_relup(RelName, ToVsn, UpFromVsn, Config) when is_list(Config) ->
diff --git a/src/rlx_relup.erl b/src/rlx_relup.erl
index 0a1e0ce5d..a5b341004 100644
--- a/src/rlx_relup.erl
+++ b/src/rlx_relup.erl
@@ -6,6 +6,10 @@
 -include("relx.hrl").
 -include("rlx_log.hrl").
 
+%% Ignore Dialyzer warnings on this, `no_warn_sasl` is a valid option
+%% but the `systools:make_relup/4` spec is outdated and this causes
+%% warning as late as OTP-28, and all calls in the chain fail analysis in turn.
+-dialyzer({nowarn_function, [do/4, make_upfrom_script/4]}).
 -spec do(atom(), string(), string() | undefined, rlx_state:t()) -> {ok, rlx_state:t()} | relx:error().
 do(RelName, ToVsn, undefined, State) ->
     OutputDir = rlx_state:base_output_dir(State),