As mfkne says, the other way around is very common - long name on passport, shorter name on tickets.

As long as it is clear these are separate names, it should not be a problem - especially as you have the email from the airline. I'd print that out and bring it with you - to give you comfort / help you relax.

You don't mention the departure country, where are you boarding the flights? Some countries won't give it a second glance, others might look for a moment. Generally countries where this kind of thing is normal (long names, only partially on documents) are used to it.

(The group of people to feel really sorry for are people who have two passports, but different names used on each!)


Ultimately - you alerted the airline to your concern, they said it was no problem. So you should be fine.

Just make sure any "advance passenger information" you supply matches the details of the travel documents you will be using. (Not all routes require API).