CONGRATS FOR THE WIN AGAINST BARCA. YOU'RE A HUGE CLUB. (I had to say that.. sorry)
This is how au works with the old method:
1. when you tune to a channel, emu gets the srvid.
2, Then it searches ALL groups that have an ecm key with the same srvid.
3. Then it gets the emm keys from the groups matched in 2. But not all. It starts adding emm keys until it reaches 32. Then it stops adding any more.
This can have some drawbacks as they are explained in note 3:
For example, lets suppose you want to run auto update for afn (9.0E). You tune to a channel from afn with srvid 68. This srvid also exists in the discovery group in 4.8E (I think). This means that the emm keys from these 2 groups (afn and discovery) will be added for au! If you have the discovery group above the afn in your softam.key, then the discovery emm keys will be added first. If they are for example 20 in total, then the final 12 positions will be filled with the emm keys from the afn group. So only the last 12 emm keys are the correct ones, and au has to find ecm keys only using these 12emm keys in practice. If you had 32 emm keys in your discovery group, then all emm keys would have been chosen from it. So, the au will not find any new ecm keys for afn.
The 2nd problem with the old design is that if the same emm key is present in 2 or more groups. the ecm keys in the wrong group could be updated. Take the previous example. If the same emm key is present in both the afn and the discovery groups, and an emm packet comes for this emm key, then the emu will not know which group's ecm keys to update. It will update the ecm keys in the first group it finds in softcam.key, which will be the discovery ones, the wrong ones.
These two problems can be avoided, if you have a smaller number of emm keys for each group in your softcam.key and if you make sure that the same emm key is not present in more than 1 group.
With the new method, these problems do not exist. We match the group from the start, so there is not margin for errors. And we can actually use all 32 emm keys for the correct group for au.