We are living in a digital age -we use every possible medium of communication - emails, phone call, support ticket. Although we try to keep some method to madness. We have internal SLAs and TATs to address our customer needs based on multiple factors like account size in terms of dollar value and if they are part of specific program.
Having said that, each program has a specific TAT (Turn-around time) and SLAs. We advice you to review your specfic program so that you have realistic expectations in terms of communication.