All Southern depots run to the same shift patterns do they not?
Selhurst have 03:59 starts (there are 00:39 and 02:40s but they are Link 1 and you won't see them for at least 10 years anyway). Look on the bright side, any start pre 05:00 you can't work more than 8.5 hours, so even if you start 04:00 the latest you can finish is 12:30, a nice afternoon to do as you wish. Latest finishes are about 2ish. There are two night turns too, one is a load of Preps at Streatham Hill, and one is a Staff train turn which is very quiet.
The depot is very friendly and generally people tend to moan about the work (still not really sure why) rather than the personnel, the same of which can't be said about some other depots who have a reputation.
And as for overtime, generally it is there if you want it. It has been very rare for me to put in for working a Rest Day and not get anything.