Idk, I probably made it up! Or maybe I'm confusing it with the driving theory? I thought I had read it here somewhere...I get all of my info from UKY! That's good to know though...maybe I'll get more serious about studying for it now in preparation for my citizenship. Still have 2 1/2 years to go, but doesn't hurt to plan early, right?
You'll need to pass the Life in the UK test for ILR, too.
I definitely recommend taking it sooner rather than later. You never know what life's going to throw at you a few years down the line and it's good to get it out of the way. Also, they're not going to make it easier or cheaper, so there's no point in waiting!
The same advice applies to driving licences in the UK.
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Get it over and done with as soon as you can.