Wondering if there's a way to get rid of an error in Apple Script to mount server
I'm really only a beginner to scripting, but I'm wondering why you have so much code in your script.  I was able to accomplish the exact same results with using only a couple of commands.  

mount volume "smb://192.168.2.66/"
do shell script "hdiutil attach -noverify '/Volumes/Data_Smokestack_ATC/James’s MacBook Pro.sparsebundle'"


I have both of my Airport Time Capsules set with static IPv4 addresses, so their IP’s never change (so I always know how to connect to them if I need to)

The do shell script part of my code waits until the mount volume command completes, therefore, I did not need to insert a delay command. On my system using the latest version of macOS Sierra,  if I run this code again while the volume is already mounted, this script just quietly completes with no errors or messages.  

That said, my thought is wouldn't it just be more “code efficient” to run these two lines of code inside of a repeat loop at 15 minute intervals for 12 or 24 hours or something like that? Then to be saved as a stay open application?