If you are accepted as a Second Officer (1 stripe), you will be based in Hong Kong for the entire time. There is only temporary basings for SO's. Upgrade to Junior First Officer (2 stripes) is NOT guranteed at 3 years. It is when the company deems you qualified for upgrade, not sooner, not later. The average is generally about 3 years. You then will sit as a Junior First Officer for another period of time, (months to years, depending on the individual) before you are promoted to First Officer (2 and 1 half stripes). You will be a FO for a number of years before you are promoted to Senior First Officer/ Relief Commander (three stripes). You will sit as a SFO for a number of years before you are promoted to Command. A new hire on the passenger side can expect command on the passenger side in about 12-15 years if hired this year. This is a realistic time frame, if you are above average in skill, and can tow the company line.
All promotions are based on company discretion, NOT on seniority.
No, not all get the 744. All SO's are split between the A340 and B744, based on the needs of the company.