Issue
Lent is treated slightly differently across the Catholic Rites.
In the Melkite Rite, the Great Lent begins on the Vespers of Clean Monday, which is the Monday after Ash Wednesday (Feb 19th this year), and ends on the Friday after the 5th Sunday of Lent. This is precisely 40 days, counts Sundays and has stricter a stricter abstinence obligation than the Latin Rite form of Lent. Namely, that abstinence be practiced on all days of Lent except for Palm Sunday and the Feast of the Annunciation.
In the Roman Catholic Rite, lent begins on Ash Wednesday and ends on Holy Thursday. This includes Sundays only as far as our conscience dictates.
Question
If someone is baptized, given first communion, and confirmed as a Melkite Catholic, but has otherwise grown up in the Western Rite, does Melkite doctrine state that there can be a choice in which Lent a believer chooses to follow?