EEA4 Eligibility - Temporary Time Abroad

[sheep]

Hi all,

I'm the holder of a RC (EEA2) with my wife currently exercising her treaty rights in the UK as a worker. My residence permit was initially granted on account of my wife being a long term exchange student in the UK, however she will soon need to return to her home country for a 4 month period in order to conduct research for her thesis and complete a final internship in order to receive her diploma. We will of course be visiting each other during this time, but I would like to make sure that my current status as well as eligibility for permanent residence further down the line is not jeopardised. Precisely:

> Is there something I need to be aware of in terms of my wife's status during this time? In other words, will she come under self-sufficiency (thereby requiring us to hold CSI during that time) or is this rendered irrelevant given that she is temporarily in another EU state?

> What relevant evidence should be retained during this time that may be needed for an EEA4 application later on?

Many thanks