Updating a Company Blog
Great question! And @Secespitus raises some good points as well. However, I'd like to add a few additional things you might want to consider.
Best Practices of Business Blogging
In today's atmosphere where everyone is trying to create content to attract as much traffic as they can, the last thing that is needed is more content articles. What is needed though, is more relevant, high-quality content.
That said, I agree with Secespitus that you should double-check with the company or blog's editor whether or not there are company protocols or precedents regarding the format of the blog.
If no precedent exists, you can generally gain cues from the comments people have left in the past and any follow-up questions they had can give you an idea of how the audience prefers updates to be made. In ANY case, if you update an article, ALWAYS make a note of it!
If Google Does It, It's a Good Idea
The above screenshot is from Google's own Webmaster's Blog. Smart money says that if Google is doing it on their own blog, then it's either a requirement or a good practice
to get in the habit of(if you want to rank well in Google's SERPs (search engine ranking pages).
Don't Forget to Optimize for Mobile-friendly Search
When writing or updating a business blog, it's vital to keep SEO in the forefront of your mind. It's fairly easy to much up your SEO by not paying attention to what you're doing.
Here are a few tips to avoid hurting your SEO when updating a blog article
Do NOT change your URL/Slug: If you can avoid changing the URL by not altering the slug (ex: www.yoursite.com/best-practices-Blog), then keep the URL intact. Otherwise, the new URL will not get any of the SEO juice from the old post which will now be a 404-Page Not Found Error. No Bueno!
If you must change the URL, be sure to correctly redirect the old URL to the new one
using a 301 Redirect so you get all that good "SEO Juice" flowing to the updated URL.
Using HTML to Scroll to a Link on the Same Page: Update/Replace the old information with the current & correct information where appropriate in the article. But, be sure to document the update/revision with a footnote marker & cite the source at the bottom of your post/article.
If you wanted you can also use HTML to automatically scroll to a specific point on the page. Here's a decent article explaining How to Link Within The Same Page. Use this to link from your Update Notice at the top of your article to the updated portion of the page.
- Keyword Relevance: Be sure to stay on task with your pages keywords and not to mistakenly weaken your pages SEO by cannibalizing your current keyword strategy. Updates should boost SEO signals not weaken them.
Hopefully, this helps you with your updating tasks. Just remember, most important to your SEO to Google and Bing respectively, is useful, accurate, well-developed content that your readers engage with.