As far as whether there are changes from year to year, there have been some (and this is one of those perks that Disney has the option of ending). The rates, $50, $95 and $35 have been the same for several years. The general seasons have also been the same. However, that April 20 date for beginning of the low "summer" rate is a first this year as in prior years the peak rates ran to the end of April and summer rates usually began on the last couple of days of April or May 1. Also, here is some additional info:
1. The annual card actually costs close to $91 after you add tax.
2. That card can actually last longer than a year. It expires at the end of the month one year from the month you buy it. Thus, if you purchase a card say on March 1, 2003, it will be valid through March 31, 2004 and thus if you go at the same time each year it is possible to use it for two annual trips.
3. You can make tee times up to 90 days in advance except for the peak mid-Jan to April time when it is 14 days (that allowance has changed frequently for that peak time as in some years it was 60 days and then it became only 2 days in advance and now it is at 14). Play is limited to after 10 a.m. rounds all year and take that "after" 10 literally as the discount does not apply to a 10 am tee time.
4. How much you really save per round depends on season and course. Osprey is the most expensive course, followed by Eagle Pines and then Magnolia, Palm, and Lake Buena Vista are usally the same price. The savings is actually lowest during the summer. The $35 rate sounds great for after 10 times but from May through September, Disney's regular rates for after 10 a.m. rounds are usually only $45 for the Magnolia, Palm, and LBV, $50 for EP and $60 for OR. Highest savings is actually in the peak season when you pay $95 because Disney's regular rates run from $135 (for the three lower ones) to $160 for OP. The fall rates have savings in between those two. The big quirk this year is that short April 20 to end of April period where you will only pay $35 -- Disney will likely still be charging its peak regular rates till end of April and thus the savings for that brief time will be huge.
5. As you should note from the above, whether you should actually get the card depends on how often and when you will play. What you have to calculate once you estimate how many times you will play in a year is what your actual total savings per round will be to see if it exceeds the price of the annual card. For example, if you just plan to play once in a year's time it is not worth it. Moreover, if you usually go in summer, you really need to play a lot of rounds to justify the card -- for example, play 4 times at LBV and you save only $40 total for the rounds and that does not justify paying $91 for the card. Of course if you have multiple players (like you and three guests) the total savings accumulates quicker.
6. Also be aware that there are Disney Club and Annual Passholder discounts (20% off regular rate) and those can be used for before 10 a.m. times.
7. Disney provides transportation, usually a taxi, to and from the course to any guest staying at a Disney resort (
DVC is irrelevant to that).