I decided to dive into my timetable database for you to compare the May 2004 with the May 2005 schedules:
View attachment 617620
Basically, what happened is that prior to May 2005, VIA operated a very different morning schedule on weekdays and weekends, where the morning train from Sarnia would operate on weekdays via Brantford (Train 82) and on weekends via Kitchener (Train 682). In May 2005, Train 682 became daily (and was renumbered 84), which was the opportunity to systemize the timetable by operating the early morning Sarnia train daily via Kitchener, like it already operated on weekends. Nevertheless (and as you already remarked), a connection was offered in London to transfer between Train 84 and 70, which lasted until November 2021 (when the departure time of Train 84 in Sarnia was delayed at the request of Metrolinx from then 06:10 to 08:40):
| Train # | May 2004 (weekdays) | May 2004 (weekends) | May 2005 (weekdays) | May 2005 (weekends) |
|---|
| 86 | 05:25 LNDN
06:44 KITC
08:20 TRTO | | 05:20 LNDN
06:41 KITC
08:20 TRTO | |
| 82 | 05:25 SARN
06:34 LNDN
07:26 BRTF
08:25 LNDN | | 05:25 SARN
06:34 LNDN
07:26 BRTF
08:25 LNDN | |
682
(May 2005: 84) | | 06:10 SARN
07:18 LNDN
08:40 KITC
10:05 TRTO | 06:45 SARN
07:44/54 LNDN
09:11 KITC
10:52 TRTO | 06:45 SARN
07:44/54 LNDN
09:11 KITC
10:52 TRTO |
| 70 | 06:00 WDON
07:58 LNDN
08:59 BRTF
10:04 TRTO | 06:00 WDON
07:58 LNDN
08:59 BRTF
10:04 TRTO | 06:00 WDON
07:53/58 LNDN
08:59 BRTF
10:15 TRTO | 06:00 WDON
07:53/58 LNDN
08:59 BRTF
10:15 TRTO |
And for what it's worth, offering a SARN-TRTO train via Brantford rather than Kitchener was really an anomaly, which only lasted from June 1998 until May 2005, as a curious deviation from the division of all SWO services into a northern (SARN-LNDN-KITC-TRTO) and southern route (WDON-LNDN-BRTF-TRTO) which has persevered since the 1990 cuts:
Well, there actually is regular bus service between London and Sarnia (
The Municipality of Strathroy-Cardoc operates a bus
2-3 times per day from London and Flixbus operates 6 times a week all the way from Toronto via London):