I often play the Zenith Daylong Reward event on the BBO. It is a robot event with robots sitting in three axes while the human participant plays as South. There are 16 deals. There is 1BB$ entry free that effectively keeps away many casual players. Eighty percent (80%) of the collected entry fee is given away in prizes of BB$ so there is something to play for however small that reward may be. You also get some BBO points for finishing in the leaders' list. It takes me about 30 minutes to finish the set in one go. I can always logoff in the middle if something comes up. I guess one hour is the maximum it takes even if you have couple of breaks in between.
As for Bridge, the robots of 199x vitage, updated with lots of ongoing minor tweaks here and there is what you get to play with. Robots only play standrd American and the Bidding is sub-par, but the play, once the robots get the hang of the hand is almost perfect. In the 16-deal set, there always are a couple of deals that are worth discussing.
In the linked video, I discuss my results on 17th June. I also discuss a couple of deals that presented interesting problems.
Click here to watch....