A friend bought a flight one month ago (with Turkish) and now he has renew the passport and the number is different. He's wondering if he could take the flight showing both passport, the old one (invalidated) and the new one. Or does he need to make a booking change and pay the tax?
The check-in desk never checks the passport number, so he's good to go.
Source: flew with Turkish after getting a new passport.
So is the old Passport Number somewhere on your booking? If yes probably call to ask, one would imagine when asked for the details the operator/website will warn if your passport expires before the journey as you surely would've been asked for the dates on the passport.
On EasyJet friends have told me that they've entered Identity Card IDs on their bookings but passed checking and boarding with a different Passport with no problem, after asking the attendants about it at the airport.