With tonight's episode, the foreshadowing for Jon's resurrection seems pretty conclusive. It seems that the most likely way it'll go down is by Melisandre early next season, but there is an issue. Knowing the show, there needs to be a clear and established precedent for whatever happens; look at the sudden mentions of greyscale before the stone men for example.

The last time resurrection was mentioned in the show was, I believe, season 2 (unless you count Robert Strong). This means that D&D will likely want to establish that resurrection is possible by red priests. There is only one other red priest they've shown in Westeros, and that's Thoros of Myr.

The last episode is titled "Mothers Mercy", and as a lot of people have pointed out, that is one of LSH's nicknames. I believe that D&D could use the BWB and Lady Stoneheart to remind viewers of the powers of red priests before resurrecting Jon. It's not guaranteed but I think it is possible.

So GET HYPE.