That was the case in the past, but you can do up to 10 years now.From memory, and I might be wrong, you can only lock a .UK (NOMINET) for two years.
Personally I would avoid using .uk domains for any critical services as Nominet is a strange organisation that has odd ways of doing things.
That is by far the most important point.You do not need to register the domain name with the same company that hosts your domain space.
Domains are one thing. Email accounts are another. Web hosting is another. Who you get an internet connection from yet another one.
All of those could be obtained from one place but it isn't necessary or even desirable to do so.
Same applies to VOIP phone service - if you want a 'landline' equivalent you can buy it from any provider, not just who you pay for broadband.
