Determining your era when modelling in Ho scale is a matter of preference. Whatever you choose, there is a chance you'll find out what you want in the long run.
In S scale, you got to tailor your goals according to what is available or doable. In my case, finding freight cars isn't exactly a walk in the park, but nice stuff like Fowler boxcars, early steel twin hopper cars and good old wooden gondolas and truss rod boxcars and reefer can be found or scratchbuilt.
However, finding decals is another matter and as you can't do everything, I decided to see what was available. I was lucky to find a bunch of CDS Lettering dry transfers for classic Canadian roads of the day: Canadian Pacific, Canadian Northern, Grand Trunk/GTP and Intercolonial. These cars were often seen in the area back then. However, there is a catch. Most decals represent cars in service between 1906 and 1914. While I set my era in 1911, it means I should push the date forward to the eve of the Great War. It seems 1913 would be my safest bet. Does it change anything on the layout? Nothing at all but it's good to know that at that time, the National Transcontinental Railway was now serving Edmundston and interchanging with Temiscouata. Also, it wouldn't be out of place to see a motor car by the station at this date and newer railway designs such as the Fowler car can run on the layout without creating discrepancies.
For Temiscouata, the decals available are all for cars repainted in the mid 1930s. I think the reporting marks and data can be salvaged.
And as crazy as it sound, I love dry transfer. I used to hate them until I made a bunch of cars last summer for a friend's layout. When you know how to work with them, they are much pleasant than decals which always leaves some weird ghosting whatever you do. Dry tranfers also works better on real wood cars than waterslide decals.
As for locomotives, given S Scale is a rich man's world, I decided it was better to start of with one excellent model rather than waste my resources on many of them. I'm convinced a good old time 4-4-0 will do the job better than anything else. It will have to be built from scratch so I'm in no hurry. In that regard, I've examined many old Temiscouata locomotives and it is evident that in the 1910s, their boiler jacket sheeting had got a serious amount of abuse over the time. They were no longer the new kids on the block and I feel it would be neat to model boilet jacket full of scratch and dent. I've never seen that kind of weathering and think it would be very neat to represent an old lady doing her last waltz on the dance floor.
To be noted, I don't expect to work on S Scale projects in earnest before next fall. My schedule is loaded beyond control until then and I'll be happy if I can buy and build a freight car. I must admit I'm lured by the idea of building a Ridgehill Intercolonial Fowler boxcar.
Until then, I'll concentrate my efforts on Hedley-Junction and building my new 1:1 workshop. I reworked my design from last year to look more like a 1890s-1910s building. I'm seriously thinking about applying wainscotting and moldings to the second floor future train room to get a nice turn of the century railway look. The main floor will be the real workshop and I plan to have a comfortable space for modelling. I think most people would be facepalming if they knew I'm modelling and airbrushing on my computer desk which generally have no more clear space than a 1 square foot area!!!