[James2001]

Yeah, just looked on STV Player, it's still in SD (which does suggest that's how the show was made), but the quality difference is night and day. Here's the end caption from the same episode- UKTV Play on top, STV on bottom- on STV Player the text is significantly sharper, and the caption a lot further from the bottom of the screen:




Even just from a screenshot of white text on a black background, it shows what a mess UKTV's handling of SD content is right now.  How this isn't being noticed really is bizarre.

Can compare the two versions of the same episode for yourself:

uktvplay.co.uk 
player.stv.tv