Debug error when clicking Re-check all versions on ACP manage extensions page

[phpBB Debug] PHP Notice: in file [ROOT]/phpbb/version_helper.php on line 274: Undefined index: announcement

			// Replace & with & on announcement links

			foreach ($info as $stability => $branches)

			{

				foreach ($branches as $branch => $branch_data)

				{

					$info[$stability][$branch]['announcement'] = str_replace('&', '&', $branch_data['announcement']);

				}

			}