{% load i18n %}
<li>
    {% ifchanged %}
        <div class="date">{% trans "day" %} {{o.when|date:"l, d/m/Y"}}&nbsp;</div>
    {% endifchanged %}
    <p>
     <span class="time">{{o.when|date:"H:i"}}</span>&nbsp;&nbsp;-&nbsp;&nbsp;
     <span class="title">{{o.what}}</span>
     </p>
</li>


{% load i18n %}
<li>
    {% ifchanged %}
        <div class="item-context">{% trans "day" %} {{o.when|date:"l, d/m/Y"}}&nbsp;</div>
    {% endifchanged %}
    <p>
     <span class="time">{{o.when|date:"H:i"}}</span>&nbsp;&nbsp;-&nbsp;&nbsp;
     <span class="title">{{o.what}}</span>
     </p>
</li>


Use item-context for event date
Use item-context for event date
