That is my assumption as well, these are retired people, so time is not an issue. The 3 MHz stations become active early in the evening and can be heard until sunrise. The mediumwave music pirates also have I wide span of operation times. On weekdays, I mostly listen to them in the morning Moscow time (at night for me). Many Greek pirates are also active at any time of day, although the reasons are likely different. Where have you heard Siberia around 14 MHz? In the ham bands? The only pirates I have heard from there are the stations that QSO on 10460 USB (I have only heard they are from Siberia, I cannot verify that myself).