<% content_for :title, raw(finder.name) %>

<header>
  <h1><%= raw(finder.name) %></h1>
  <% if finder.primary_organisation %>
    <div class="metadata">
      <dl class="inner-block">
        <dt>From:</dt>
        <dd>
          <%= link_to finder.primary_organisation.title, finder.primary_organisation.web_url %>
        </dd>
      </dl>
    </div>
  <% end %>
</header>

<%= render finder.facets %>
<div class='js-live-search-results-block'>
  <div class="filtered-results">
    <div class="inner-block">
      <p class="result-info" aria-live='polite' id='js-search-results-info'>
        <%= render_mustache('result_count', @results.to_hash)%>
      </p>
      <div id='js-results'>
        <%= render_mustache('results', @results.to_hash) %>
      </div>
    </div>
  </div>
</div>

<% content_for :title, raw(finder.name) %>

<header>
  <h1><%= raw(finder.name) %></h1>
  <% if finder.primary_organisation %>
    <div class="metadata">
      <dl class="inner-block">
        <dt>From:</dt>
        <dd>
          <%= link_to finder.primary_organisation.title, finder.primary_organisation.web_url %>
        </dd>
      </dl>
    </div>
  <% end %>
</header>

<%= render finder.facets %>
<div class='js-live-search-results-block'>
  <div class="filtered-results">
    <div class="inner-block">
      <p class="result-info" aria-live='assertive' id='js-search-results-info'>
        <%= render_mustache('result_count', @results.to_hash)%>
      </p>
      <div id='js-results'>
        <%= render_mustache('results', @results.to_hash) %>
      </div>
    </div>
  </div>
</div>

Use assertive not polite here
Use assertive not polite here

So the new result count is announced immediately rather than waiting for the user to move focus off of the checkbox they've just selected.
