Logistics question

Perfect storm this weekend.
I 've got two batches to bottle today and I’m brewing a batch Saturday that I want to rack directly onto the yeast cake from one of todays batches.

1, Do I rack the beer off the cake, replace the airlock, and let it sit for roughly 24 hours and just rack the new wort on top of it? Infection risk?

2, Do I rack the beer, clean the yeast cake, make a small starter and let it run for 20 hours?

No need to make a starter. I would save the yeast cake in a sanitized container and pitch it in your new brew tomorrow. Depending on your batch size and gravity, you probably don’t need to pitch the entire cake.

I’ve got quart jars of sanitized water for washing, dump the water, pour the cake into the far, close tight, refrigerate/don’t refrigerate?

Yes.
:cheers: