Disabling iMessage while travelling I will be travelling overseas without mobile data. International SMS will be set up, but I have iMessage linked to this mobile number. I have other iPhones, iPads and Macs which also receive iMessages on this account.

Do I have to disable iMessage on all my devices before I travel to ensure when people send a message to my mobile number, I will receive it as an International SMS?

Thanks in advance.
Simple answer, yes.
If you want SMS to arrive at your phone there must be no other device left active that can possibly pick up the iMessage.  

Otherwise Apple considers that if any device received the iMessage, it is considered delivered &amp; will not try again as SMS.

Related question - How to tell Messages &quot;I&#39;m not at home&quot;? which remains unanswered, despite the great efforts of one member; but shows promise for Yosemite, if not Mavericks.