diff --git a/plugins/generic/announcementFeed/AnnouncementFeedGatewayPlugin.php b/plugins/generic/announcementFeed/AnnouncementFeedGatewayPlugin.php
index a802c0cbca1..9dcafdfbf6d 100644
--- a/plugins/generic/announcementFeed/AnnouncementFeedGatewayPlugin.php
+++ b/plugins/generic/announcementFeed/AnnouncementFeedGatewayPlugin.php
@@ -16,8 +16,8 @@
 namespace APP\plugins\generic\announcementFeed;
 
 use APP\template\TemplateManager;
+use Carbon\Carbon;
 use PKP\announcement\Announcement;
-use PKP\core\Core;
 use PKP\db\DAORegistry;
 use PKP\plugins\GatewayPlugin;
 use PKP\site\VersionDAO;
@@ -139,14 +139,14 @@ public function fetch($args, $request)
         $lastDateUpdated = $this->_parentPlugin->getSetting($journal->getId(), 'dateUpdated');
         if ($announcements->isEmpty()) {
             if (empty($lastDateUpdated)) {
-                $dateUpdated = Core::getCurrentDate();
+                $dateUpdated = Carbon::now();
                 $this->_parentPlugin->updateSetting($journal->getId(), 'dateUpdated', $dateUpdated, 'string');
             } else {
                 $dateUpdated = $lastDateUpdated;
             }
         } else {
-            $dateUpdated = $announcements->first()->getAttribute('datePosted');
-            if (empty($lastDateUpdated) || (strtotime($dateUpdated) > strtotime($lastDateUpdated))) {
+            $dateUpdated = $announcements->first()->datePosted;
+            if (empty($lastDateUpdated) || $dateUpdated->gt($lastDateUpdated)) {
                 $this->_parentPlugin->updateSetting($journal->getId(), 'dateUpdated', $dateUpdated, 'string');
             }
         }
diff --git a/plugins/generic/announcementFeed/templates/atom.tpl b/plugins/generic/announcementFeed/templates/atom.tpl
index a184b535ede..0cff2f4a3c3 100644
--- a/plugins/generic/announcementFeed/templates/atom.tpl
+++ b/plugins/generic/announcementFeed/templates/atom.tpl
@@ -36,21 +36,21 @@
 {foreach from=$announcements item=announcement}
 	<entry>
 		{* required elements *}
-		<id>{url page="announcement" op="view" path=$announcement->getKey()}</id>
+		<id>{url page="announcement" op="view" path=$announcement->id}</id>
 		<title>{$announcement->getLocalizedData('fullTitle')|strip|escape:"html"}</title>
-		<updated>{$announcement->getAttribute('datePosted')|date_format:"%Y-%m-%dT%T%z"|regex_replace:"/00$/":":00"}</updated>
+		<updated>{$announcement->datePosted->format("%Y-%m-%dT%T%z")|regex_replace:"/00$/":":00"}</updated>
 	  	<author>
 			<name>{$journal->getLocalizedName()|strip|escape:"html"}</name>
         </author>
-		<link rel="alternate" href="{url page="announcement" op="view" path=$announcement->getKey()}" />
+		<link rel="alternate" href="{url page="announcement" op="view" path=$announcement->id}" />
         {if $announcement->getLocalizedData('description')}
-		<summary type="html" xml:base="{url page="announcement" op="view" path=$announcement->getKey()}">{$announcement->getLocalizedData('description')|strip|escape:"html"}</summary>
+		<summary type="html" xml:base="{url page="announcement" op="view" path=$announcement->id}">{$announcement->getLocalizedData('description')|strip|escape:"html"}</summary>
         {/if}
 
 		{* optional elements *}
 		{* <category/> *}
 		{* <contributor/> *}
-		<published>{$announcement->getAttribute('datePosted')|date_format:"%Y-%m-%dT%T%z"|regex_replace:"/00$/":":00"}</published>
+		<published>{$announcement->datePosted->format("%Y-%m-%dT%T%z")|regex_replace:"/00$/":":00"}</published>
 		{* <source/> *}
 		{* <rights/> *}
 	</entry>
diff --git a/plugins/generic/announcementFeed/templates/rss.tpl b/plugins/generic/announcementFeed/templates/rss.tpl
index 4da99e0720e..7e9e2b7a610 100644
--- a/plugins/generic/announcementFeed/templates/rss.tpl
+++ b/plugins/generic/announcementFeed/templates/rss.tpl
@@ -34,24 +34,24 @@
 		<items>
 			{foreach from=$announcements item=announcement}
 			<rdf:Seq>
-				<rdf:li rdf:resource="{url page="announcement" op="view" path=$announcement->getKey()}"/>
+				<rdf:li rdf:resource="{url page="announcement" op="view" path=$announcement->id}"/>
 			</rdf:Seq>
 			{/foreach}
 		</items>
 	</channel>
 
 {foreach from=$announcements item=announcement}
-	<item rdf:about="{url page="announcement" op="view" path=$announcement->getKey()}">
+	<item rdf:about="{url page="announcement" op="view" path=$announcement->id}">
 		{* required elements *}
 		<title>{$announcement->getLocalizedData('fullTitle')|strip|escape:"html"}</title>
-		<link>{url page="announcement" op="view" path=$announcement->getKey()}</link>
+		<link>{url page="announcement" op="view" path=$announcement->id}</link>
 
 		{* optional elements *}
 		{if $announcement->getLocalizedData('description')}
 		<description>{$announcement->getLocalizedData('description')|strip|escape:"html"}</description>
 		{/if}
 		<dc:creator>{$journal->getLocalizedName()|strip|escape:"html"}</dc:creator>
-		<dc:date>{$announcement->getAttribute('datePosted')|date_format:"%Y-%m-%d"}</dc:date>
+		<dc:date>{$announcement->datePosted->format("%Y-%m-%d")}</dc:date>
 	</item>
 {/foreach}