On your Optik STB connected to your 4K TV ensure that you update the 'aspect ratio' setting. The setting should actually be called 'resolution', but regardless of it's name, set it to "2160p 60hz 4K". If your TV can support 2160p the setting will be applied. If not you will be asked to select another setting. Next time you watch 4K contenct, the resolution will be supported and TSN4K will look better than TSN1 (see my later comment).
When you see a message on your TV about "HDR" it means that 4K HDR content is passing through your AV network to your TV and your TV detects it and can play it for you. Most of Netflix 4K content is HDR these days, that's why you see the "HDR" message when watching Netflix on your Smart TV. You should also see this message from your TV when watching Netflix directly via your Optik set top box (STB) or when watching 4K HDR On Demand on your Optik STB.
Lastly you commented on TSN1 vs TSN4K. When there are 4K broadcasts (actually filmed/produced/broadcast in 4K resolution) our guide will provide the programming details. You can also find the TSN 4K broadcast schedule online. During all other times, the guide will say something like "next live event [date]" and will provide some high level info on the sport and teams scheduled to play. During those times, you still see content. This is typically TSN4 or sometimes TSN1 (not sure why it changes) HD programming shown on their 4K channel (TSN4K). It's not broadcast in 4K, but I think it's passing through 4K equipment and gets "upconverted". Maybe I'm just imagining it, but IMO it looks better, sharper, on my Samsung, and if what I want to watch happens to be on TSN4K that's my channel of choice despite the extra bandwidth I'm using.
Hope this helps.
