<h1 class="heading">Fri 18 Jun</h1>
<table>
 <tr class="tablerow">
  <td class="tablecell"><span class="date-span">Fri 18 Jun<span></td>
  <td class="tablecell"><span class="date-span">Sat 19 Jun</span></td>
 </tr>
</table>

<h1 class="heading">Fri 19 Aug</h1>
<table>
 <tr class="tablerow">
  <td class="tablecell"><span class="date-span">Fri 19 Aug</span></td>
  <td class="tablecell"><span class="date-span">Sat 20 Aug</span></td>
 <tr>
</table>

$(".date-span").filter(function() {
return $(this).text() !== $(".heading").text();
}).closest('.table-cell').remove();