You could go either way and still be fine, I think. I hadn't heard that delaying solids could lead to jaw and speech problems...that's a new one for me! If it were me, I think I'd go ahead and start her now, or you could even wait a couple more wks. You would know pretty quickly if she had a reaction to solids, and that would mean that she's not ready yet or that particular food didn't agree with her.
As for when you're on holiday, it's actually pretty easy to keep up solids. I wouldn't introduce any new foods while you're away, just keep rotating through what she's already had and done well with. You could easily just give her different kinds of infant cereals mixed with breastmilk, formula, or water the entire time you're away. That would keep things really simple. If you hadn't given her jars before your trip, I don't know if I'd try them for the first time while you're away, given her prior reactions to formula. If there's a store nearby, you can easily pick up some very ripe bananas or avocados and mash them up really well with breastmilk or formula. There are also lots of inexpensive mini blenders that are battery operated and small enough to fit in your diaper bag. You can take one with you to get a really good, smooth puree from very ripe fresh fruit.
I also found that in those first couple months of solids, it was easy to be flexible. Before we started solids, he'd let me know LOUDLY at the 4 hr mark when he was hungry. On solids, we were able to be more flexible with his eating times, since he ate so much more often during the day and never got super hungry.
