Multiple VIPs on one VS

How about just creating a file as described by BockyBoy above:

tmsh list ltm virtual | sed -r -e 's/^ltm virtual ([^\{ ]*)/ltm virtual \1_tmp/g' -e '/vs-index .*$/d' > /shared/vs_tmp  

In /shared/vs_tmp you will find a list of all current virtual servers with the extension "_tmp" in their name. Now it´s just about to modify the destination IPs i.e. via vi and to merge the modified file to the running configuration, save and sync.

tmsh load sys config merge file /shared/vs_tmp  
tmsh save sys config

If you can provide a list of old and new addresses by a i.e. comma separated file it can easily be used as a sed-dictionary to automatically replace all destination IPs in the merge file. Please let me know, if I can help with it.