Hi Leo,
The times and routes are the same on Mo/We/Fr and different but the same on Tu/Th/Sa.
The first arrival of the day into Sheffield is from York Thralls Europa and then they head off to places like Wrenthorpe Recip, Bridlington, Hull and Grimsby returning to Sheffield at least once later in the day. They reverse in USS or DS1 at Sheffield.
With a little judicious searching on RTT (freight services only) you should be able to work out all the times from this.
Be aware some RHTTs will finish in the next two or three weeks.