I've checked both editpost.php and the template and they seem fine.
Code:
<if condition="$GAS_is_article">
<!-- byline field -->
<table cellpadding="0" cellspacing="0" border="0" class="fieldset">
<tr>
<td class="smallfont" >$vbphrase[GAS_byline]:</td>
</tr>
<tr>
<td><input type="text" class="bginput" name="articlebyline" value="$articlebyline" size="40" maxlength="85" tabindex="1" /></td></tr>
</table>
<!-- / byline field -->
</if>
That is what I have in the template for the byline field.
Where in particular in editpost.php should I be checking?