Hi Tim,
I have set up a toll free number that I give out to my customers rather than my actual number. The toll free number is almost always forwarded to my cell phone, however, I can change that and forward it to another number anytime I want. So if I go somewhere for a few days where my cell service is poor or nonexistent, I at least have the option of forwarding my customers’ calls to a better phone. To utilize this flexibility, you would need a good phone at your vacation spot of course.
I know this doesn’t solve your problem and you couldn’t implement this immediately as your advertised number is already out in ads, etc., but you might want to look into this for the future. I have the toll free service set up through Kall8. You can do everything you need to do online at http://www.kall8.com.
I should point out that the calls to me through Kall8’s service cost me, but it is a very small amount per minute. Our business is not particularly phone intensive, so the cost of the service is mostly neglible.
Have a good time on your vacation!
Mike