How to place a placeholder for date and time in html? - html

Question

I am working on html email in which I want to place a placeholder for dynamic contents. The snippets of code from html email where I have used dynamic contents are:
<tr>
<td>
<table cellpadding="0" cellspacing="0" border="0" width="100%" style="color:#484848;font-family:'Champagne & Limousines';font-size:20px;padding-left:5%;">
<tr>
<td style="padding-bottom: 3%;text-align:right;">type:</td>
<td style="padding-bottom: 3%;padding-left: 8%;">{{availability_check_request}}</td>
</tr>
<tr>
<td style="padding-bottom: 3%;text-align:right;">estimated total:</td>
<td style="padding-bottom: 3%;padding-left: 8%;">{{estimated_total}}</td>
</tr>
<tr>
<td style="padding-bottom: 3%;text-align:right;">what</td>
<td style="padding-bottom: 3%;padding-left: 8%;">{{what}}</td>
</tr>
<tr>
<td style="padding-bottom: 3%;text-align:right;">how many</td>
<td style="padding-bottom: 3%;padding-left: 8%;">{{how_many}}</td>
</tr>
<tr>
<td style="padding-bottom: 3%;text-align:right;">when:</td>
<td style="padding-bottom: 3%;padding-left: 8%;">{{when}}</td>
</tr>
<tr>
<td style="padding-bottom: 3%;text-align:right;">who:</td>
<td style="padding-bottom: 3%;padding-left: 8%;color:#FF8D58;">{{who}}</td>
</tr>
</table>
</td>
</tr>
Problem Statement:
I am wondering what placeholders I would be using for:
March 28/18 # 7:00pm to March 30/18 # 7:00pm
At this moment, in the code above I have used {{when}}. Is it should be {{$date_from}} to {{$date_to}} ?