diff --git a/app/assets/images/exclamation.svg b/app/assets/images/exclamation.svg
deleted file mode 100644
index e530210e1..000000000
--- a/app/assets/images/exclamation.svg
+++ /dev/null
@@ -1,26 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Generator: Adobe Illustrator 21.1.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
-<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
-	 viewBox="0 0 17.5 14.5" width="17.5" height="14.5" style="enable-background:new 0 0 17.5 14.5;" xml:space="preserve">
-<style type="text/css">
-	.st0{display:none;}
-	.st1{display:inline;fill:#BCBCBC;}
-	.st2{fill:#FFFFFF;}
-	.st3{fill:#6F777B;}
-</style>
-<g id="Layer_3" class="st0">
-	<rect x="-1.6" y="-0.8" class="st1" width="20.1" height="17.8"/>
-</g>
-<g id="Layer_1">
-	<path class="st2" d="M8.6,0L0,14.5h17.5L8.6,0L8.6,0z"/>
-	<g>
-		<circle class="st2" cx="8.8" cy="10.9" r="1.1"/>
-	</g>
-</g>
-<g id="Layer_2">
-	<path class="st3" d="M8.8,10.3c-0.8,0-1.5,0.7-1.5,1.5c0,0.8,0.7,1.5,1.5,1.5s1.5-0.7,1.5-1.5C10.2,11,9.6,10.3,8.8,10.3L8.8,10.3z
-		"/>
-	<path class="st3" d="M10.1,5.8C10.2,6.6,9.8,9,9.8,9S9.4,9,8.8,9C8.3,9,7.8,9,7.8,9S7.3,6.7,7.3,6c0,0,0-1.6,1.4-1.6
-		C10.1,4.4,10.1,5.8,10.1,5.8z"/>
-</g>
-</svg>
diff --git a/app/assets/stylesheets/components/broadcast-message.scss b/app/assets/stylesheets/components/broadcast-message.scss
index 672ce5207..71bfd20f7 100644
--- a/app/assets/stylesheets/components/broadcast-message.scss
+++ b/app/assets/stylesheets/components/broadcast-message.scss
@@ -21,19 +21,23 @@
     position: absolute;
     top: -1px;
     left: -1px;
-    padding: govuk-spacing(2) + 1px govuk-spacing(3) (govuk-spacing(2) - 1px) 46px;
+    padding: govuk-spacing(2) + 1px govuk-spacing(3) (govuk-spacing(2) - 1px) 15px;
     border: solid 1px transparent; // to show it's area in high contrast mode
     width: calc(100% + 2px); // grow to overlap wrapper's border (when combined with top and left)
     box-sizing: border-box;
     font-weight: bold;
-    background: $grey-1 file-url('exclamation.svg');
+    background: $grey-1;
     color: $white;
-    background-size: 22px;
-    background-repeat: no-repeat;
-    background-position: govuk-spacing(3) 11px;
     border-top-right-radius: 5px;
     border-top-left-radius: 5px;
     box-shadow: inset 0 -1px 0 0 rgba(0, 0, 0, 0.1);
+
+    &__icon {
+      padding-right: 6px;
+      // user agents set this to 'none' by default for svgs so set as 'auto' to allow
+      // colours to be overridden in forced-color modes like Windows high contrast mode
+      forced-color-adjust: auto;
+    }
   }
 
 }
diff --git a/requirements.in b/requirements.in
index 7343ca794..81053f579 100644
--- a/requirements.in
+++ b/requirements.in
@@ -30,7 +30,7 @@ pyproj==3.2.1
 # PaaS
 awscli-cwlogs>=1.4,<1.5
 itsdangerous==1.1.0  # pyup: <2
-notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@49.1.0
+notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@50.0.0
 govuk-frontend-jinja @ git+https://github.com/alphagov/govuk-frontend-jinja.git@v0.5.8-alpha
 
 # cryptography 3.4+ incorporates Rust code, which isn't supported on PaaS
diff --git a/requirements.txt b/requirements.txt
index feba75754..94cece298 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -123,7 +123,7 @@ mistune==0.8.4
     # via notifications-utils
 notifications-python-client==6.3.0
     # via -r requirements.in
-notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@49.1.0
+notifications-utils @ git+https://github.com/alphagov/notifications-utils.git@50.0.0
     # via -r requirements.in
 openpyxl==3.0.7
     # via pyexcel-xlsx