Hello Nina and others,
As you are well aware, there exists many timelord (chronocrator) systems in Hellenistic astrology i.e. profection, decennials, quarters of the moon, lunar monomoiria, zodiacal aphesis, etc. It is my understanding that any one of these timelord techniques can be used with:
1. the natal chart to determine the areas of life affected during the lordship of these timelords and
2. with solar return and transits to pinpoint the timing more precisely.
Some of the timelord techniques can be divided into major (covering span of years), minor, sub-minor, sub-sub minor etc. For example, the profection and zodiacal aphesis methods can give us the year lord, month lord, day lord (and some claim even hourly lord). Note that I use the term daily, hourly etc. loosely because sometimes a day lord can cover 2 and a half days, and so on and so forth. For a major lord that covers span of more than one year, the position of transiting Saturn must also be analyzed. For a year lord, Jupiter should also be carefully analyzed for the year prediction as well as the Solar Return chart (because nataurally this covers a year). Transiting Mars, Sun, Venus and Mercury must be observed with the monthly lord. Lastly, the day lord should be analyzed with transiting moon.
Firdaria is not one of the Hellenistic timelord techniques. It is probably persian but it is the simplest there is! You need to carry only 2 tables (one for diurnal and one for nocturnal births) and if the native has a natal chart (or if you plot for them), you're in the astrological prediction business.
The big question then is, "Which timelord is to be used?". Traditionally speaking, once the timelord procedure has been selected we can then call upon our solar return and transits to be more precise. Some astrologers suggest using all of the timelord techniques each with different objectives covering different areas of life. I find this very confusing as you will end up having almost all planets the timelord of something and everything. This is the same objection I have for astrologers who say that marriage is governed by trip rulers of Venus, lord of 7th house, first trip lord of 7th house and lots of marriage (and there are lots of lots of marriages!). Even if we remove Venus (as being the universal ruler) we still end up with more than a couple significators to choose from!
My feeling (and this is only my feeling) is that the ancients must have "designed" or discovered that different timelord schemes are to be used for different natives (not all timelords are to be used for one native covering different areas of life). I suggest that planet based natives (those who answer strongly to either luminaries) should use planet based timelord techniques (e.g. decennials for solar influenced natives, quarters of the moon for lunar influenced natives or even firdaria). Natives who strongly answer to ascendant should probably use profection (from ascendant of course!) or even circumambulation (also from ascendant). Natives who are strongly lot based should then give more emphasis to Zodiacal Releasings.
The timelord based on Firdaria depends only on where the sun was at the time of birth. If it was above the horizon (diurnal chart) then you start with sun and if it was below the horizon (nocturnal chart), you start with moon. This suggests that Firdaria as timelord should be used with natives who are strongly solar or lunar.
The idea is that to determine how a firdar ruler (and perhaps subruler) will manifest is to look at the Solar Return for the year that the ruler first becomes active. So if your Saturn period began in 1995, you would look at the condition of Saturn in the 1995 Solar Return horoscope to get a sense of how it would manifest.
Let us assume that the major period of Satrun begins in 1995. It should then end in 2016. The condition of Saturn in 1995 Solar Return when you are under Saturn Period is definitely important but I think it should be limited only for that year. I would look into both the major and minor firdaria in the Solar return chart to see their effects for the year. But 3 years later the minor firdaria will be different (though the major firdaria is still Saturn). I would then look into Saturn (the major Fridaria) and the minor firdaria planet in the corresponding Solar Return chart for yearly predictions. Saturn is the timelord for 11 years in the firdaria system. The general conditions of Saturn in the
natal chart tell us the conditions of the 11 year period (whether
generally good or bad). The conditions of Saturn in the Solar Return tell us the yearly conditions - more specific.
The timelord system tells us which planets to emphasize (for whatever period). Looking into these emphasized planets (the timelords) in the solar return chart limits the emphasized planet as timelord for one year. If the timelord is still active the following year, we still look into this timelord but we look into the new solar return chart.
Having said these, let me briefly outline what other professionals have said on Firdaria:
When I was first exposed to firdaria, I was taught to use the approach outlined by Robert Hand (I don't if he still hold this view). He likened the major and minor periods to Matter and Form (Aristotelian definition of Matter and Form). So, if you are under Mars/Venus fridaria (Mars = Major and Venus = Minor), the matter is Mars but the form is Venus. The whole seven years are governed by Mars - fire, cutting, discord, quick release, etc. but what does Mars cut/burn/release/...? The areas governed by Venus (as the form). Another way of looking at this is to look where Mars is in the natal chart. The Matter (major firdaria planet) is the house location of where Mars is. If Mars is in the 3rd house, then matters governing the third will be the Matter for Mars/Venus firdaria. The houses that Venus rule (by domicile and exaltation) are the Form for Mars/Venus Firdaria. Using this concept, the period of Mars/Venus firdaria will be totally different from Venus/Mars firdaria.
Another concept that I have seen is the one presented by Jonathan Pearl who uses the major and minor firdaria planets as new derived ascendant and delineate the natal chart accordingly. Assume that you are in Mars/Venus Firdaria. Take the sign where Mars is and use this sign as ?new? ascendant for the next 7 years (Mars major firdaria). Then take the sign where Venus is and use this as the ?new? ascendant for the next one year (any minor planet period in Mars firdaria major period is given one year).