diff --git a/CHANGES b/CHANGES
index 99fcf27f8b..3e5b866ff8 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,11 @@
+
+3.3.0-dev.554 | 2020-11-19 18:09:01 -0800
+
+  * Reverts the SMTP regex change in dead3226a545e264072ced40284f86ac41528ba8. (Tim Wojtulewicz, Corelight)
+
+    The regex change broke some of the external tests. I added some more cases
+    to the regular email btest to hopefully cover all of the cases better.
+
 3.3.0-dev.551 | 2020-11-17 15:01:04 -0700
 
   * Added unit tests for regex fix (christina23)
diff --git a/VERSION b/VERSION
index 40e3177ad6..131a01122e 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.3.0-dev.551
+3.3.0-dev.554
diff --git a/scripts/base/utils/email.zeek b/scripts/base/utils/email.zeek
index 903048eafd..b647149bdc 100644
--- a/scripts/base/utils/email.zeek
+++ b/scripts/base/utils/email.zeek
@@ -19,7 +19,7 @@ function extract_email_addrs_vec(str: string): string_vec
 ##
 ## str: A string potentially containing email addresses.
 ##
-## Returns: A set of extracted email addresses.  An empty set is returned 
+## Returns: A set of extracted email addresses.  An empty set is returned
 ##          if no email addresses are discovered.
 function extract_email_addrs_set(str: string): set[string]
 	{
@@ -58,8 +58,7 @@ function extract_first_email_addr(str: string): string
 function split_mime_email_addresses(line: string): set[string]
 	{
 	local output = string_set();
-
-	local addrs = find_all(line, /(\"[^"]*\")?[^,]+@[^,]+/);
+	local addrs = find_all(line, /(\"[^"]*\")?[^,]+/);
 	for ( part in addrs )
 		{
 		add output[strip(part)];
diff --git a/testing/btest/Baseline/scripts.base.utils.email/output b/testing/btest/Baseline/scripts.base.utils.email/output
index 6955547403..dc0958ff64 100644
--- a/testing/btest/Baseline/scripts.base.utils.email/output
+++ b/testing/btest/Baseline/scripts.base.utils.email/output
@@ -1,3 +1,4 @@
+### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
 one@example.com
 [one@example.com, two@example.com, three@example.com, one@example.com]
 {
@@ -22,6 +23,12 @@ two@example.com
 john.smith@email.com
 [john.smith@email.com, jane.doe@email.com]
 {
-john.smith@email.com
+john.smith@email.com,
+jane.doe@email.com
+}
+john.smith@email.com
+[john.smith@email.com, jane.doe@email.com]
+{
+john.smith@email.com,
 jane.doe@email.com
 }
diff --git a/testing/btest/scripts/base/utils/email.zeek b/testing/btest/scripts/base/utils/email.zeek
index 5177ce8cb2..6d4838765f 100644
--- a/testing/btest/scripts/base/utils/email.zeek
+++ b/testing/btest/scripts/base/utils/email.zeek
@@ -19,3 +19,7 @@ s = "\"Smith, John\" <john.smith@email.com>, \"Doe, Jane\" <jane.doe@email.com>"
 print extract_first_email_addr(s);
 print extract_email_addrs_vec(s);
 print extract_email_addrs_set(s);
+s = "\"Smith, John\" <john.smith@email.com>,\"Doe, Jane\" <jane.doe@email.com>";
+print extract_first_email_addr(s);
+print extract_email_addrs_vec(s);
+print extract_email_addrs_set(s);