How you communicate with customers is vital to the survival of your business. Choose a reliable phone system for your office, so your customers can always reach you. In the event of inclement weather, you can route calls to your cell phone, too.
I got a new cell phone recently. As the world stood in line to pick up the latest iPhone 8, I graduated to the 6S. I pride myself on that actually. As with all new phones in the 21st century, the voicemail must be set up anew. I used the default message for the first few days, but finally settled down to record a more personal greeting.

To provide as much helpful insight to businesses as possible, we've compiled the top must-have information that should be included in your office's temporary voicemail greeting. 1. Your voicemail should be timely and relevant to the situation at hand. 2. Indicate if you’re working remotely or changing office hours temporarily. 3. Set clear, reasonable expectations for your callers about when they should expect to hear back from someone. 4. State clearly what types of matters are urgent and give examples of issues that are not. This way, patients and callers can have a good understanding of what to expect about call-backs and reduce unnecessary follow-up calls. 5. If you have made disruptions to existing appointments, you should note this, as well as how you plan to reach people to reschedule.
SIP is what's used for the vast majority of modern VoIP phone systems. It also handles phone service, video conferencing, and several other tasks just fine, which is why its use is so widespread. Where it has trouble is data security, but more on that in a bit.