I did a year abroad as an undergrad, it was my first big trip and living in another country (haven't stopped since, life changing experience).
I went to California, so quite a long way to go when first leaving home! I did it in style!
I had a return trip booked for Christmas, it was an awful trip back! The weather, the sudden lack of interesting exciting life and my new me. Some of the international students stayed, no one was on their own, some booked trips together, some were invited to spend the holidays with families of friends, some booked solo travel joining an organised group. They all had a wonderful time and I would really recommend this. Absolutely will not be alone!
Those of us who travelled back couldn't wait to get back, I changed my travel dates to be back sooner. It's also a time to really grow up and see the world as a place can explore, developing huge independence and confidence that stay for life if embraced. So I think being there for holidays is a good idea and will be amazing fun. Plus, how often in life will she get to have that traditional holiday or not go far and be in dream destination ski places with local or international friends. Lots of international students will stay to enjoy and take advantage of the time.
I remember at the time it was a big deal for me to go so the idea of four months until coming back made it gentler, but I absolutely would not do it again that way, I didn't want to do it once I'd gotten there but the way my flights were booked meant I had to. Otherwise I would have much preferred to stay, it's incredibly precious time, I'd advise any student with the opportunity to absolutely make the most of it.
I'd also say make the year as long as possible, my visa was still valid throughout the summer, so when classes finish after this amazing time, take advantage! There's a good chance the place will become a second home, or very close to their heart, it's such an incredible opportunity and memorable time in life, so really make the most of it!
Maybe book a round trip (flexible) for the whole year, say get the Christmas flights nearer the time, once you know what you like to do, in case (hopefully!) you get an amazing opportunity and want to do that instead?
Seriously, she should enjoy it and really take advantage, it was one of the happiest and most personally defining and shaping times of my life! I never looked back:)
(Hello from the seventh country I've lived in, every single one has my heart and I'm fearless with opportunities, all because one day when I was really young I somehow found the courage to get on that plane!)