Toad 13.1.0.78: On RAC environment, TOAD shows instance ID at the connection info. When you are disconnected from network and press Session -> Reconnect, instance ID remains, but you can be signed to different instance ID (load balance on RAC). Instance ID is wrong in this situation.
Thanks for letting us know. Our Support/Dev team members will pick this up, if they haven’t already documented the issue from others, and prioritize for resolution in our release map.
prioritize for resolution in our release map.
That's awfully formal. I decided to just fix it. 
I tried to reproduce this by:
- Make a connection to a RAC instance (It gave me instance #1)
- disconnected that session from another copy of Toad.
- In the first copy of Toad, clicked Session -> Test Connections.
- I was reconnected to instance #2, and the [2] was indicated on the connection button.
Can you provide some more detail? Where in Toad are you seeing the wrong instance # shown?
I got this error from my colleague. I tried to reproduce it too few minutes ago, and it was working well on my TOAD 12.12.0.39
My colleague is on vacation now, he will be back in 2 weeks. I am going to ask him to try to reproduce it again on his TOAD 13.1.0.78 when he will be back. He is very experienced user, so I didnt checked it - I am sorry for that, next time I’ll check every reported bug from my colleagues before posting them here.
My colleague retried it and it works as expected. I am sorry for false report.