Optimum is the first landline telephone service provider in the U.S. to launch High Definition calling. HD calling is the next generation of voice technology that gives you less background noise, sharper sound quality and increased clarity in your phone conversations. To experience HD calling, customers and call recipients must subscribe to Optimum Voice and use HD-capable handsets.
20. "Hey there, this is [your name] from [your company]. I'm out of the office until [date]. In the meantime, please direct your inquiries to [coworker's name] at [email address]. They can also be reached at [phone number]. Thank you."

Doing this gives your prospects the assurity that you will follow up with them which makes them drop in their contact details for you to reach out to them.
You might take this as a good sign: people have realistic expectations, and you don’t have to feel pressure to pick up the phone right away. But the reality is that this means people see phone calls as a big commitment. They’re setting aside a block of time just to ask a quick question. And the bigger the commitment it is to interact with your business, the fewer interactions you’re going to have.