Ash kitchen island top, help!

Hi, I’m a newbie to this forum as I’m looking for some advice from some of the more experienced folks on here!

I’ve been working with timber for many years but haven’t built an island top as big as this before. I’m joining four pieces of Ash together. They are all 9’4" long and the following widths: 22", 12", 12" and 18". All are approx 1.5" thick and i’m joining them together using tongue (0.25" ply) and groove with 2 part epoxy, sash clamped whilst cure takes place.

I know the joints will be strong as hell but because its so big and needs carrying about a bit to its resting place, i’m wondering if I need to also use worktop connecting bolts (routered into underneath) and also considered 3 large ones made with threaded bar to run full width.

I don’t want to make work for myself and do this unnecessarily so any thoughts/advice are appreciated. Finished size 9’4" x 5’4" x 1.5" thick.

Thanks in advance!

James