I would say she may still be reacting tot he pepti jumior. The next stop is Neocate.
The proteins are more broken down in Neocate which make it much easier to tolerate.
My dd2 had severe reflux and bottle aversion. It took us 6 months to get her on Neocate and enough Losec, and by then her aversion was so severe she stopped taking bottles altogether. I spoon fed her milk mixed with farex from then on - so not fun.
Have you thought of seeing a private Paed? One that has experience with reflux. If you are in Auckland I have the name of a few. One in paricular is great. I can't give it to you here, but if you want it I will PM you it.
I found vaccinations really upset my daughters reflux and for week afterwards her feeding was terrible.
What is she doing when it is feeding time?
One thing I foudn worked with both my refluxers was to feed them when they were either sleepy or totally asleep. They would be relaxed enough to take it.
4-6 months is the worst time for reflux too, so she is right in the middle of that.
What dose of losec (omeprozole) is she on?
Aldo lots of people have had trouble with the generic brand and have need to pay to get Losec brand. It can make a huge difference.
Big hugs, it is such hard work!