PookeyMaster,
There is a requirement under part 6.41 of the regulations to report a conviction of an Aviation Security Relevant Offence.
I agree that given the cost of these things, the two year validity sucks. Given that the regs were changed only about a year ago to change validity to the end of the month in which the clearance is given instead of the last day of the previous month, I can't see moving much more on the issue. I would like to be proven wrong though.