I agree with the PP. My cell phone number has been our "primary number" with doctors, dentist, school, etc. forever. We still have a land line since it's free (would cost more to disconnect it as we lose a bundle discount). The funny thing is the only calls we get on our "house phone" is telemarketing calls and cheesecake factor calls (cause they miss printed a flyer once). I actually had it unplugged for close to a year. When I did happen to plug it back in, it was just telemarketing and cheesecake factory calls again. My husband has a cell phone from his work that gets crappy service in our neighborhood. So if his cell phone drops he might call me back on the "house phone" otherwise it is not even used.
Just start updating your primary number with the offices that you are most concerned about with your number or your spouse's number. I choose mine cause DH works in a secure area that he can't have his cell phone inside his work building, so he turns it off and leaves it in his car. So that just leaves my cell as the primary.
I actually prefer the cell phone as the primary because most appointment reminders come via text vs call. The only one that calls is the orthodontist the day before appointments. Our family dentist, hair salon, facial spa, massage spa, tutor, etc. also does the text reminder where you can respond with "c" to confirm, etc. Even the high school I get a text notification with "important reminders" where it provides a link to listen to the recorded message from our school superintendent.