Yes, one is {1CD85...}, the other is {C60DC...}.
I keep 42 revisions based on my previous conversation with Symantec support. The explanation is the following :
Symantec releases 3 definition updates a day. If I keep 3 revisions, that means that only the clients which have the previous day's definitions are able to refresh themselves with minor update files. All the others need to download the whole definition which is more than 100MB. In my environment there are several mobil users connecting via low bandwidth lines to my SEPM server, so I decided to keep 14 days to be able to serve them smoothly.
I am using this config almost a year, without any size problems. Recently, I noticed that the usually 3-5GB directories went up to 15+GB.