IB got back to me. Said it was the autolog off time (it was not).
Then insisted it was the following issue …
Initial Description: TWS logged out
Response from IBCS at 05-May-2022
Adding to the previous response we would like to inform you that the time you mentioned coincides with the server reset time for your region. This reset happens for server maintenance. For further information please refer to the following link : https://www.interactivebrokers.com/en/software/systemStatus.php
Regards,
Abhay I
IBKR Client Services – Technical Assistance Center
Will see what happens tonight. Hopefully it was a one off.