Ofcom have released the amateur radio licence statistics for September 2013 showing a further rise in numbers
The grand total of licences at the start of September was 81888 an increase of 87 over the August figure.
Since 2006 possibly as many as 3,500 UK radio amateurs have died and they would have been expected to drop out of the statistics, but month after month the numbers that Ofcom report show a steady rise.
There is no way of telling how many amateurs have simply given up the hobby in the past 7 years or how many amateurs there really are. The rumour mill may suggest that fewer than 25,000 amateurs have renewed their licence but the statistics do not tell us.
On March 14, 2013 a response to a Freedom of Information Request stated that "Ofcom have not carried out another extension." [of the licence], but it seems they haven't revoked any license either.
Ofcom UK Amateur Radio Licence Statistics - http://licensing.ofcom.org.uk/radiocommunication-licences/amateur-radio/guidance-for-licensees/monthly-stats/
How to validate your licence - http://www.essexham.co.uk/news/remember-to-validate-your-licence.html