Is the procedure for transiting the new Bangkok airport different from the old one? How segregated is landside and airside these days?

I plan to embed a BKK-TPE-BKK MR on KL (arriving back into BKK sometime between 22-23h) and then leave on NW27 at 06h the next day, and don't think a hotel for a night is worth it given what time I'll get to a hotel and what time I'll have to leave to get back to the airport.

Assuming I've printed my all BPs, can I assume that I can remain airside and go to the departure level or is the new airport more bureaucratic than that? Do I have to wait at a transfer desk?