From the other side of phone: call my office phone unless something we did is shutting your line down.
I never answer my cell for business even if it's sitting right in front of me ringing. If you haven't had the courtesy to call my desk phone first, be prepared to leave a message. On the other hand, I will ALWAYS answer my desk phone.
Note: my email signature and my business card both say that the cell is the secondary number. I have piss poor coverage on my cell where I work and that's if I'm in the front office. If I'm in the plant, I have zero coverage. Hence the stipulation that the cell is secondary.
And don't even think about text messaging... I pretty much ignore any work related text messages and that even applies to my boss as well.
Yeah, I'm an old curmudgeon and if work pisses me off enough, I'll fucking retire right now.