In the Syriac (Malankara Syriac) churches there is no liturgy on weekdays of Great Lent with the exception for four days:
Thanks for this. So I would suppose the practice of not celebrating the Liturgy during Lent is a Syrian practice (the Byzantine rite also being a variant of the Antiochian), which is why one doesn't find it in the Alexandrian rite churches, whereas the Presanctified Liturgy is a uniquely Byzantine practice. From what I understand, St. Gregory did not actually compose the Presanctified Liturgy, but merely recorded the existing practice he witnessed in Constantinople.
The following might be more appropriate in another thread since this is the OO section. That being said, the EO practices are (with minor differences) the same as those of the OO churches:
So is the traditional EO practice to fast from sunrise (Matins) until 3:00 PM? I still don't know how to do this properly.
The fast begins at Midnight, not sunrise.
Do you have a copy of Bishop Kallistos' translation of the Lenten Triodion? He gives quite an in-depth explanation of the rules of fasting, which he balances with the appropriate warnings against both Pharisaic legalism and the scorning of "these rules as outdated and unecessary [both of which] are to be deplored as a betrayal of true Orthodoxy." (p.15)
(a) On weekdays in the first week, fasting is particularly severe. According to the strict observance, in the course of the five initial days of Lent, only two meals are eaten, one on Wednesday and the other on Friday, in both cases after the Liturgy of the Presanctified. On the other days, those who have the strength are encouraged to keep an absolute fast...At the meals on Wednesday and Friday xerophagy is prescribed. Literally this means 'dry eating'. Strictly interpreted, it signifies that we may eat only vegetables cooked with water and salt, and also such things as fruits, nuts, bread and honey...the following categories of food are definitely excluded:
(ii) animal products (cheese, milk, butter, eggs, lard, drippings);
(iii) fish (i.e. fish with backbones)
(iv) oil (i.e. olive oil) and wine (i.e. all alcoholic drinks).
(b) On weekdays (Monday to Friday inclusive) in the second, third, fourth, fifth and sixth weeks, one meal a day is permitted, to be taken in the afternoon after Vespers, and at this one meal xerophagy is observed.
(c) Holy Week. On the first three days there is one meal each day with xerophagy; but some try to keep a complete fast on these days...as on the opening days of the first week.
On Holy Thursday one meal is eaten, with wine and oil (i.e. olive oil).
On Great Friday those who have the strength follow the practice of the early Church and keep a total fast. Those unable to do this may eat bread, with a little water, tea or fruit-juice, but not until sunset, or at any rate not until after the veneration of the Epitaphion at Vespers.
On Holy Saturday there is in principle no meal, since according to the ancient practice after the end of the Liturgy of St. Basil the faithful remained in church for the reading of the Acts of the Apostles, and for their sustenance were given a little bread and dried fruit, with a cup of wine. If, as usually happens now, they return home for a meal, they may use wine but not oil; for on this one Saturday, alone among the Saturdays of the year, olive oil is not permitted.
The rule of xerophagy is relaxed on the following days:
(1) On Saturdays and Sundays in Lent, with the exception of Holy Saturday, two main meals may be taken in the usual way, around mid-day and in the evening, with wine and olive oil; but meat, animal products and fish are not allowed.
(2) On the Feast of the Annunciation (25 March) and Palm Sunday, fish is permitted as well as wine and oil...
...It has always been held that these rules of fasting should be relaxed in the case of anyone elderly or in poor health. In present-day practice, even for those in good health, the full strictness of the fast is usually mitigated. Only a few Orthodox today attempt to keep a total fast...In cases of uncertainty each should seek the advice of his or her spiritual father. At all times it is essential to bear in mind that 'you are not under the law but under grace' (Rom. 6:14), and that 'the letter kills, but the spirit gives life' (2 Cor. 3:6).
St. Nikodemos of the Holy Mountain, speaking of Wednesdays and Fridays throughout the year, also says that "just as the fast of Great Lent consists in the eating of dry foods, namely, to eat but once a day, at the ninth hour, without consuming oil or wine, likewise, the fast of Wednesday and Friday is to be conducted in the exact same manner." source
Hope that helps.