I run VDR 2.0.2 on a Raspberry Pi. The device runs continuously, so to avoid wearing out the SD card or needlessly spinning-up the USB disk drive I run VDR with the -E- option to prevent saving the EPG every 10 minutes.
Today I created a timer for one programme in a long-running series and was surprised to find that the Series Link plugin had scheduled timers for earlier episodes, some broadcast several weeks ago! These timers were then automatically deleted of course.
Looking at the code, it seems that cleaning up the EPG schedules is a side-effect of writing the data file, so the -E- option disables both. Having the EPG grow unbounded is perhaps not desirable on devices such as the Raspberry Pi which have limited memory and CPU.
Dave