10 year long residence -10 months as part of BA-

Hi,

What happens if someone goes to the USA as part of their BA degree? I know a person who after her second year picked a module which involved her going to North Carolina University. She then returned to UK and finished her 4th year here.
When she left to the States she had a valid UK visa, which then expired there. She did not come back to the UK during those 10 months and got a new UK visa from the USA when her studies finished.

Now the whole thing is sponsored by the British University and Local Authority here. They even offered to pay her tickets back for Christmas (which she did not use).

She originally came to the UK in September 2003 and the USA trip happened in 2009 and apart from that hasn't broken the continuos stay.

My question is; does this break the 10 year continuos stay or does it fall under exceptional circumstances (as it is part of her British educations) ?

Thanks for any help from now
kara

Any ideas from anyone?

Any absensce more than 6 months in a year break the continuous residence.