I've noticed this problem as well but I actually think the tv guide is labeled incorrectly because based on the HGTV episode guide the episode order is
Season 1, Episode 8. Set in Stone
However, in the Xfinity Stream list, it has "The Deep End" labeled as Episode 3 and "When it rains, it pours" as Episode 6. And the episode that is coming on tonight(6/28/2020) "Power Struggle" is labeled as Episode 8. It's quite strange. I'm not sure what's going on but I watched the episodes in the HGTV episode order and all the episodes match up.
Thanks for bringing this up to our attention! We will work with our metadata provider to ensure the sequencing is correct.
@anataxi as @kgordon258 mentioned, even though the episode sequencing is not proper at the moment, the episodes are indeed sequential from 1-4 as they appear on screen. We will remediate the sequencing shortly. We apologize for this inconvenience.
The last episode (episode 6) of "No One Saw a Thing", an AMC+ (aka Sundance TV) mini-series is missing.
I did a system refresh, but that did nothing. The series info says there are only 5 episodes, but there are definitely six - https://en.wikipedia.org/wiki/No_One_Saw_a_Thing#Episodes.
Can someone from Comcast look into it?