Eea2 - home office visit?

Hello everyone!

My partner submitted an eea permit application as unmarried partner last month in June. He is a non eea citizen. We know each other since 2011, are in relationship since 2013, but living together since 09/2015 only. We still applied although there is a lack of cohabitation - that we explained is due to my studies in my eu country / already started before our relationship. Lets see if they consider it as a valid reason or not!

My question to u guys is: does the home office do surprise visits at home for this visa? What are our rights? (Im scared after what ive read and heard about them.. for ex i heard if they dont find both together at the time of visit, they arrest the applicant?!)
Im really scared about that. Im traveling quite often during the year to my eu country (my family n friends r there) so it might be possible they visit our home and I'm away? What would happen then? He is legally staying in uk, according to the rules, and we are in genuine relationship (he can provide many proofs during the visit if they ask so) - do they have the right to detain my partner if i'm not home at the time of the visit?

Ps: my partner's stay in uk is legal, his previous visa expired but he legally has the right until the new decision comes.

I might be a bit parano about it but thats because of the stuff i heard , and i dont kniw much about the rights we have in these circumstances..

Thanks for any response!