EU residency application - passport return?

[anniecc]

A friend of mine is an EU national who has been working in the UK for many years. She wants to apply for permanent residency and then citizenship as she is worried about the implications of the Brexit vote.

I understand the EU applications take up to six months and there is no premium service. Is there any way to avoid having to be without your passport for six months? I've seen some references on this site to a passport return option but I can see any info about this on the government website.

[LilyLalilu]

1) Get a national ID card and use it to travel whilst the application is processed. Should be able to get one at the Embassy, my Embassy got me one within 2 weeks. (Or send the ID card and keep the passport if overseas travel is required).

2) Request your documents back. Usually takes 10 working days but may apparently take much longer these days because they don't seem to be able to cope with the influx of applications/requests.
(First hit on google : https://www.gov.uk/visa-documents-returned)

[anniecc]

1) Get a national ID card and use it to travel whilst the application is processed. Should be able to get one at the Embassy, my Embassy got me one within 2 weeks. (Or send the ID card and keep the passport if overseas travel is required).

2) Request your documents back. Usually takes 10 working days but may apparently take much longer these days because they don't seem to be able to cope with the influx of applications/requests.

Thanks very much. Can you point me to some 'official' info about the passport return option?