In my region, ie Hants, IOW, they have advertised for weeks of a digital channel change on 25th - constant ads and a mail shot. On the day had to re tune my Lounge TV and DVD recorder,same in bedroom, and a tv in spare bedroom and my Nedia Centre PC !!
We officially switchover to full digital on November 4th this year in my area and a retune will be necessary.
However, I'm told that the actual retune is only for BBC2 and that a further full retune will be required the following month.
This is very likely to cause consternation amongst a number of people, particularly senior citizens, who may not be aware of what to do after being led to believe that the switchover retuning only has to be done once.
Note that asking your local TV shop to undertake such a retune is likely to set you back at least £25.
It is an excellent idea, and I shall be the first to volunteer - BUT, no doubt some lowlife will see the opportunity to gain access to the older members of society's homes for their nefarious activities!