It's very odd that UKBA have given your friend that information. I'm guessing that perhaps your friend spoke with a call centre agent who probably didn't know the correct answer.

I can only share with you what UKBA formally state.

1.
The fact that an applicant’s qualifying English language certificate had expired would not prevent them from using their pass notification as evidence that they had reached level B1 (CEFR) English for a settlement or British citizenship application. They would not be expected to take another English Language test, but will need to pass the Life in the UK test.
2.
If your qualification is on the list of acceptable qualifications published on our website you will not need to retake an English test. The expiry dates for those tests do not apply to settlement and citizenship applications. You should send your certificate with the application.
I doubt your friend will be 100% convinced by any advice you share with her. So perhaps the best strategy is to show her this post and suggest that she write formally to UKBA for confirmation. It's only by doing that can she feel secure that at least the English Language requirement is covered.

I believe people should always make additional action to confirm such important information.

Hope this will help