I saw someone comment on the main page how the writer is subverting common tropes (the examples were misunderstandings, love triangle hulabaloo, and drinking when sad).
If the writer is going to keep following the general K-drama romance recipe with their own twists and such, then I think the confession will happen at the end of ep 8, then a cliffhanger, and then (to subvert expectations) a simple agreement at the beginning of ep 9 from whoever has been confessed to
But also I won't be surprised if my guess if completely off target ?