Just for information, my son had 4months lefton his and hubby and myself had 3months and 6 days lefton ours when we flew with first choice/ tomson from bristol in October. emailed airline and passport office and the embassey to triple check the info we had was correct.
no problems at all but were reminded at checkin when they were due to expire and how to go about renewing them .
Thanks Wayneg, for the link to virgin - The traveller must hold a machine-readable passport in good condition which is valid for at least the period of travel.
I've decided not to renew Joshua's passport, just update the ESTA Visa from last year with our new travel details. Renew passport next year.