If you can tolerate the wait, do it!
Because people, in general are stupid, the prefix that relates to the year (I.e. 05, 06, 07, etc) is worth around £500 more than the 'Fifty' prefix, so the continuing logic would mean a '10' plate would be worth more than the '60'.
People find it hard to judge the age of cars, when the registration does not directly reference the year, apparently.

I've got no idea where I read/heard/saw this, but I owned a '57' plate at the time, so I remember listening intently!