i'm a bit new to these forums so please correct me if i've done something wrong. is the south western railway portsmouth DLC for TS2021 the same as the route that came by default in 2019 (if not, what improvements were made etc)? thanks in advance for any help you can give
They are identical. TS2019 came with a copy of that DLC, and I'm not aware of any updates that have come out for the route since then. Basically, when you buy TS, you get the base game (that has no routes or anything included) and automatically get gifted copies of the included DLCs.
I think you might mean the South Western main line from Southampton to Bournemouth. Completely different route to the Portsmouth Direct line. Uses same stock however.
Having purchased the base game, TS2021, you can add on any route and trains from previous years. The good part about this game is the backwards compatibility with previously released DLC. Note that the older routes and locos will be the same as they were when released