Don't know if I can help, but I am currently away having travelled from the UK to the US with five hour time difference a 2 1/2 yr old and a 3 month old!
I will tell you only about my baby as she is closest in age. She is a spirited baby with a hint of touchy, so I really wasn't looking forward to the flight or the travel either, but we made it and I'm dreading the return less!
Eden has been on a routine pretty much since she was born - not always successfully, but you know how babies like to disagree with us! We had a train to catch to the airport, a 2 hour wait, an 8 hour flight and an hour and a half car ride. I use a sling with her quite regularly so when she doesn't go for a nap in her cot I have an alternative to ensure she gets her sleep while I play with my other daughter. This meant that whenever I was able to move she could sleep pretty much on her routine - her A time was around an hour and a half, so she had that facing forward in her sling (I use a Kari-me) and then her hour and a half to two hour nap in the sling both on the train and in the arport. If your LO falls asleep in a buggy I guess that would work too - Eden doesn't sleep if she can see ANYTHING! She was fine and even asleep for boarding. Unfortunately I then had to sit down - so she woke up! She was still ok - I gave her a dummy for take off, but once in the air she didn't really like it at all:( Thankfully the seat belt sign wasn't illuminated apart from ascent and descent so I was able to bob about with her for the whole flight bar when she was due for a feed, or I was due for a feed
I will be honest - I didn't enjoy it, as she didn't, but I also knew it was a finite time - the worst was the middle when it still felt like such a long time! As soon as we landed she was happy again, and we went back to awake or napping in the sling. The car ride was made easier with a dummy again, but she doesn't like those either, so we were glad to arrive.
As for jet lag, the advise I received was to adopt the time zone you travel to as soon as you get there. So I did bedtime routine on the new time, which meant keeping her going til essentially midnight! (still on EASY). She was fine!!! I did DF as normal, she woke at 330am so I fed her (which I woudn't normally do) and then had to do pat shh to get her do go down again which she did as she was so tired. We got up at 6 that morning, then 630 the next, kept it low key and stuck to EASY. I was expecting it to take longer as I'd heard to allow a day's adjustment for every hour, but it was great.
Sorry for the mini novel - I'm a talker and I was dreading it so much it's fun to share how bad it wasn't!! I would say go for it and just stick with the routine as much as you can. What kind of temperament is your LO? Does he sleep on journeys in the car?
