The current time table on the Class 166 on the London Commuter route is very lackluster. All the timetable entries you can drive are under 15 minutes. Most even shorter. Would be great if these were altered so you could drive between the two stations then simply switch cab and drive back (as that is basically what is happening anyhow) instead of having to reload the map every time to start the return trip. Instead of the time table being just one trip from A to B it would instead be full round trip A->B->A, and then the duration would simply be based on how many round trips you are to do rather than doing just one leg, restarting map, another leg, restart map et.c. With X amount of round trips the timetable could have scaled up durations from 5 minutes (a single leg) to an hour or two (all depending how many round trips it would include). Anyways, really like the Class 166 and it's a great addition to the London Commuter. The time table is just way too short and feels unsatisfactory with the constant map restarting.
On the 166 timetables I've run on BML so far (albeit with issues), you can string several legs together (Reigate to Redhill, Redhill to Gatwick, Gatwick to Redhill, Redhill to storage siding until morning) but since the route takes you back off the map towards Reading, you naturally have to exit at Reigate and wait for the next train from Reading to arrive (turning around the previous train wouldn't make sense especially if there are large gaps in the RL timetable). In saying that though, I've tried the first two timetables (~12-1am) and both of them get stuck at a red when leaving Redhill to go in to the overnight storage sidings. No other trains on the tracks at those times so it isn't a traffic issue, and no response from the signaller/dispatcher either when you hit TAB.
You shouldn't have to reload the map at all. If you press the return to free roam button at the end of a service, it'll keep you in the train, and you can wait for the return/next leg of the trip. I've done Reigate > Redhill > Gatwick > Redhill > Reigate without having to reload once.
As said above, it is possible to continue your service - just press "Return to Free Roam" and you'll be exactly where you were at before the menu came up, and then you can head to the back. I do it all the time on Cathcart with the 313, and often do it on East Coastway with Lewes and Seaford services. (This usually also applies medals/score to the list, for all completed services)
