title: date function parameters Ymd
body: <pre><code>&lt;?php
  $start_current_month = date("Y-m"); 
  $from = date("Y-m-d", strtotime('-1 month', 
  strtotime($start_current_month)));
  </code></pre>
  
  <p>This gives an answer of 2017-04-01. </p>
  
  <p>But if I change line 1 to "Ym" instead. It gives an answer of 2017-04-03.</p>
  
  <p>I assume in the first instance it defaults the days to the first of the month? Can anyone shed some light on this...</p>