Quick & dirty script to grab a new copy of PHP and Microsoft SQL Plugin and swaps over config to the upgrade.

upgrade-php.ps1

param (
	[Parameter(Mandatory=$true)][string]$version
)

if( Test-Path -Path ".\upgrade-php.xml" ) {
    [xml]$configFile= get-content ".\upgrade-php.xml";
    foreach ($option in $configFile.configuration.config) {
        New-variable -Name $option.key -Value $option.value;
    }
} else {
    Write-Host "No upgrade-php.xml configuration found. Exiting.";
    return;
}

if( Test-Path -Path "${destination}\${version}" ) {
    Write-Host "Version ${version} already exists. Exiting.";
    return;
}

Write-Host "Downloading PHP ${version} from windows.php.net.";
try {
    Invoke-WebRequest https://windows.php.net/downloads/releases/php-$version-nts-Win32-VC15-x64.zip -OutFile "${destination}\php.zip";
} catch {
    Write-Host "Not found in release. Looking in archives.";
    try {
        Invoke-WebRequest https://windows.php.net/downloads/releases/archives/php-$version-nts-Win32-VC15-x64.zip -OutFile "${destination}\php.zip";
    } catch {
        Write-Host "Not found in archive. Exiting.";
        return;
    }
}
Expand-Archive -Path "${destination}\php.zip" -DestinationPath "${destination}\${version}";
Remove-Item    -Path "${destination}\php.zip";

$versionSplit    = $version.split(".");
$versionSplit[2] = $versionSplit[2] - 1;
$previousVersion = $versionSplit -join ".";

if( Test-Path -Path "${destination}\${previousVersion}" ) {
    Write-Host "Coping configuration file from ${previousVersion}.";
    Copy-Item -Path "${destination}\${previousVersion}\php.ini" -Destination "${destination}\${version}\php.ini"
} else {
    Write-Host "No previous version was found. Initating config with default settings.";
    Copy-Item -Path "${destination}\${version}\php.ini-production" -Destination "${destination}\${version}\php.ini"
}

Write-Host "Downloading Microsoft SQL Drivers for PHP from GitHub.";
$masver = "$($versionSplit[0]).$($versionSplit[1])";
Invoke-WebRequest https://github.com/microsoft/msphpsql/releases/download/v$phpmssqlversion/Windows-$masver.zip -OutFile "${destination}\mssql_driver.zip";
Expand-Archive -Path "${destination}\mssql_driver.zip" -DestinationPath "${destination}\mssql_driver";
Remove-Item    -Path "${destination}\mssql_driver.zip";
Copy-Item      -Path "${destination}\mssql_driver\Windows-${masver}\x64\*_nts.dll" -Destination "${destination}\${version}\ext\" -Recurse;
Remove-Item    -Path "${destination}\mssql_driver" -Recurse;

upgrade-php.xml

<?xml version="1.0"?>
<configuration>
  <config key="destination" value=".\php" />
  <config key="phpmssqlversion" value="5.6.1" />
</configuration>