Can't help you with how to obtain your discount on the season ticket renewal, but I can help you out with the fare change.
The annual fare change on 01 Jan only applies to tickets purchased after that date. So, buy your season ticket starting on 12 Jan now and you'll get it at 2008 fare. Buy it on or after 01 Jan and pay 2009 fares, even though the start date is the same. Likewise if you purchase an advance/off-peak/anytime ticket before 01 Jan for a journey that you're making in the new year, you'll pay the 2008 fare.
Not true, if you pre date a fare in avantix it shows the new fare if applicable