Time to Upgrade PHP Code
Bluehost wants to update the PHP version on your hosting account
Did you get an email recently from Bluehost telling you it’s “Time to upgrade your PHP Software?”
They have been in the process of upgrading their web servers (the computer your website files reside on) to only support the newest stable versions of PHP. Even though this is potentially a hassle for you, this is a good thing.
A responsibility of any web hosting company is to stay on top of technology by upgrading and patching hardware and software as needed. This is one way to keep your website secure and running optimally. Part of the web hosting service you pay for is for them to manage the web servers. If they are not keeping on top of the security of your web hosting service, look for a new host.
I am assuming that this email did not go to all of their clients, but just the website hosting accounts that are running depreciated versions of PHP5. PHP5 has not been supported since Dec 2018. This means that bugs and security vulnerabilities that have been identified, are no longer patched, fixed. This is a great opportunity for hackers to exploit websites that have not upgraded PHP.
Typically upgrades are not as significant as moving from PHP5 to PHP 7. Since 2013, PHP code has been throwing depreciated warnings in log files that MySQL extensions will be removed eventually. As of PHP 7, MySQL extension is no longer supported. This means if your website is running on a database with code that has not been modified to support this change, it is going to throw a fatal error and your website will no longer function. There are other minor PHP changes too, but the database connection is the biggest issue and why you need to upgrade PHP on your hosting account and your website code.
In the past few weeks, I have had multiple people contact me (some in a panic) because they have not kept up with keeping their website code updated and now have a business website that will not function. Depending on the size of the site, this can be a couple of hours of work, or require a complete rebuild of your website.
The email from Bluehost says they are upgrading an old version of PHP will no longer be supported. You don’t have a choice to change the version of PHP back to what worked for your site even though there may be a negative impact. You are forced to deal with this.
What to do if your website won't run on a new version of PHP?
Update Software

Hire a PHP programmer to do the upgrade.
This is where I come in. Hiring an experienced PHP Programmer (20+ years coding with PHP) that deals with issues like this daily can save you a lot of time and frustration. I’ve upgraded more websites than I can count. I’m much more knowledgeable (and less frustrating) to deal with than trying to get “front row” hosting support to walk you through changes that are needed.
Find another host that will support outdated, insecure versions of PHP.
While technically this is an option, it is such a bad suggestion that I didn’t even want to include it. Part of owning a website is maintaining it.
With website maintenance, I preach being proactive vs reactive. Keeping your website updated will avoid getting into a situation where you are forced to react when it breaks. You have no choice but to upgrade PHP on your site, otherwise it will no longer function.
If you need help upgrading, hire an experienced web developer to get your website back online fast.