No confirmed seat on e-ticket

Hi!
Yesterday I received my E-Ticket for flight Beijing-Pyongyang in 2 weeks.
But there is no Seat confirmed by Ticket. This is going to happen at Check in (no online Check in possible).
I Plan to stay in Beijing for 2 days before flying to DPRK. Am I eligible for 144 hours free Transit although there is no seat confirmed on my e-ticket?
Thanks in advance for your response.