Lagging in XP ?

[sempai33]

Hi,
I'm reading "7 days to the grave" and page 27, I can read under "Sewer Tunnel": If the PCs are lagging in experience points..." But at that moment of the story, they should be at which level? For that moment, my party will start 7 days in being charts of lvl 4.
So can you answer me what it means "lagging in experience"? Because the next encounters are only CR7 and CR8 so they should be lvl 5 or 6 no?
Thanks a lot,
Sempaï

[primemover003]

Even though my group hasn't started playing yet CotCT's first few chapters really seem like they'd work well when you let the tension simmer in the city for a few weeks or months. This gives you time to really get the PC's involved with the NPC's like Captain Cressida or the depressed guardsman (Orsino's student) or Vancaskerin.

I'm planning on running several side treks (and using the PFRPG's slow advancement table) and letting the situation fester! One of my PC's is an abyssal heritage sorcerer that worships Pharasma so Seven Days will be a great one for him!

[Illessa]

When I ran the Sewer Encounters my party had just hit 5th level (and blitzed it in a single casting of haste!)