I have a network card which costs £25 for the year and within an area loosely described as "SE England" (the old BR Network South East) I can get discounts on rail fares, subject to certain restrictions.
I can't get discounts before 10 a.m. on weekdays. Also, my understanding was that I can't get weekday discounts to a value lower than £13 after the discount has been applied. At weekends there is no time restriction or lower limit on the fare value which can be discounted.
However, twice recently I've had a discount on midweek tickets. On both occasions it was a Friday and we'd travelled from Prittlewell after 1 p.m. That means that we have to buy a Permit to travel, the ticket office being closed, and pay the difference at Lpoo Street. When Mrs. Wow and I went to The Cycle Show, we paid about £23 between us for travelcards, and on Friday Dez & I paid £17.70 between us for cheap day returns.
I'm not complaining, I'm just confused.