re: P trap help - how would you repair?

I'll give them props for properly venting your island (chicago/loop vent) and not just throwing a studor vent under there.

If you want to avoid cutting in a tee or using the socket saver there is another option if you have the space.

For the record, nickel and dime repair (teflon/pipe dope) may also stop the leak but my brain doesn't work that way towards plumbing like it might towards trades I'm not as well versed in, and it wouldn't be considered a fix, just a bandaid.

The other option would be to cut out your recently installed p-trap as close to "A" as possible (give yourself some work space by unhooking the disposal). Leave as much of pipe "B" intact as you can. A 2" fitting needs a maximum of 3/4" for full insertion. If pipe "B" is 3/4" or more (a hair under that is fine too) glue a 2" coupling onto pipe "B". Glue a 2x1-1/2 bushing into the coupling. Glue an 1-1/2" male trap adapter into the coupling/bushing. Buy a $6 SJ P-trap from any hardware store and an 1-1/2" extension tailpiece to be sure you don't have to go back.

In a perfect world, all glue joints are behind a wall. Hope this helps. Tight spaces are never fun