This was my first thought, and I am now on the horns of the dilemma of if being faithful to Kelleher is more important than the raised percentage chance of the win with Alisson.
He'll stick with Kelleher in the League Cup as he did a couple of years ago. Personally I'd play Alisson in every game because why not use the best goalkeeper around? Maybe I'm old fashioned though because I've never really got all the 'cup keeper' and 'has to play sometime' stuff
I don't really have a problem with Kelleher playing though, he's one of the stronger backup options you could have and it is nice to keep him satisfied with a bit more game time that he couldn't get last season with us going out of both cups early. For me though, it's just as much about who you play in front of him, if you make four changes and they're all young lads then it's obviously going to be a struggle against most sides, if you keep experienced leaders in there then it'll probably go a lot smoother. I'd go next to full strength against West Ham and hopefully do the same in a potential semi final/final.
In the European knockouts which you'd expect us to make, I'd certainly go back to Alisson though, would be foolish not to play some good European sides without your number one.