From memory (2018), you won’t see what’s available til AFTER you choose Wednesday or Thursday. You will then see a range of locations some which will let you select tickets and likely some that will be unavailable or maybe sold out. It’s good coach ticket practice to have a day, then 1st, 2nd, 3rd choice of location. When we went for coach we targeted Thursday from Reading and got lucky pretty fast.
With the timings… you won’t hear what they are until much much later (maybe not until May) and the timings can be nasty. We were in a 6am out which worked great for us as we were already arriving late.