Windows 8.1 app exists in Windows 10 Store, but not in Windows 8.1 Store
<p>Detailed explanation:</p>

<ol>
<li>Windows 8.1 targeted app package bundle for x86 and ARM architectures was uploaded to the Windows Store;</li>
<li>Windows Store <em>approved</em> it as a valid app, and published it using targeted distribution (Beta release for specific e-mail addresses), and gave me two different links for each Store: Windows 10 - <strong>www.microsoft.com/store/apps/some_code</strong>; Windows 8 - <strong>apps.microsoft.com/windows/app/some_other_code</strong>;</li>
<li>Both links redirect to the same page in the web version of Windows Store (and instantly opens the Store App with the game page open): <strong>www.microsoft.com/en-us/store/games/game-name/another_code</strong>;</li>
<li>When you click the Windows 10 store link on Windows 10 machine, the Store App opens, and app is downloaded smoothly and easily;</li>
<li>BUT when you open the link to the Windows 8.1 Store on a Windows 8.1 machine, Store App opens, refreshes one time, but instead of displaying the app page, it shows the Home page, and <em>you cannot download the app at all from the official Windows 8.1 Store</em>, even though the browser page <a href="http://i.stack.imgur.com/KVSCo.png" rel="nofollow">includes Windows 8.1 in supported OS'es list</a>;</li>
</ol>

<p>Some additional comments:</p>

<ul>
<li>in <em>both</em> machines I am connected to the Store using an account, which is in the list of targeted distribution partners (e.g. in the "whitelist" of beta users);</li>
<li>App is <em>working normally</em> both on Windows 10 and Windows 8.1 when I am installing them using the ".ps1" PowerShell script Visual Studio generates when building a release package;</li>
<li>I tried to change regions in the Store (UK, LT, US, etc.), but none of them works.</li>
</ul>

<p>If you need more information - comment, I will try to explain more details :)</p>