Official Notification from Google as follows;
This email was sent because you have a consumer (personal) Google+ account or you manage a Google+ page.
In December 2018, we announced our decision to close the consumer version of the Google+ product for use in April 2019 due to the low rate of use and the difficulties we face in maintaining the product success in a way to meet consumer expectations. We'd like to share with you the next steps, including thanking you for being a part of Google+ and how to download your photos and other content.
On April 2, your Google+ account and all the Google+ pages you create will be closed and relevant content will be deleted from your consumer Google+ account. Your photos and videos on Google+ will be deleted from your Album Archive and Google+ pages. You can download and save your content before April. Please note that your photos and videos backed up in Google Photos will not be deleted.
It may take several months to delete content from Consumer Google+ accounts, Google+ Pages, and Album Archive. Therefore, some content may remain during this time. For example, users can continue to see parts of their Google+ account through the activity log, and G Suite users can see some consumer Google+ account content until the Google+ consumer version is deleted.
As of February 4, you will not be able to create new Google+ profiles, pages, communities, or events.
See the complete FAQ page for more detailed information about the process of using the product and learn about updates.
If you are a Google+ Community owner or moderator, you can download and save your Google+ Community data. From the beginning of March 2019, each community publication in public communities will be able to download additional data, including author, body text, and photos. More information
Please note that if you use the Sign In with Google+ button to sign in to sites and applications, these buttons will no longer work in the coming weeks. However, in some cases, these buttons may be replaced by the Google Login button. You will be able to sign in with your Google Account wherever you see the Sign In button. More information
If you've used Google+ for comments on your own sites or other sites, we'd like to remind you that this feature will be removed from Blogger on February 4 and from other sites on 7 March. All of your Google+ reviews on all sites will be deleted from April 2, 2019. More information
If you are a G Suite customer, the Google+ that you use with your G Suite account will continue to be active. For more information, contact your G Suite administrator. Soon a new look and new features will be added. More information
If you're a developer who uses Google+ APIs or a Google+ Sign-in system, click here to learn how this change will affect you.
As a Google+ team, we thank you for making Google+ such a special place. We are grateful to the group of talented artists, community creators and opinion leaders who adopt Google + as their home. We couldn't have done it without your passion and determination.
Google LLC 1600 Amphitheater Parkway, Mountain View, CA 94043
This mandatory e-mail service announcement has been sent to inform you of important changes to your Google+ Page product or account.