Survey of Air Travel to Edinburgh

I've observed some website:

STA Travel:
The house lease will start at 8 Sep. (A Saturday before the semester starts), so I'd better get there around that day.

The student rate from STA does not have the trip BKK (7 Sep.) -> EDI (8 Sep.). I'm not yet figured out how to range search on this site yet.

British Airways:

• Bangkok (7 Sep. 00:45) -> Heathrow (7 Sep. 7:00)
• Heathrow (7 Sep. 13:15) -> Edinburgh (7 Sep.) 29,885 THB
  
• Heathrow (7 Sep. 15:15) -> Edinburgh (7 Sep. 16:35) 29,885 THB
  
• BA0010 Bangkok (8 Sep. 00:20) -> Heathrow (8 Sep. 6:20)
• BA1442 Heathrow (8 Sep. 11:15) -> Edinburgh (8 Sep 12:35) 30,720 THB
  
• (more but not transfer at Heathrow)

Air France:

• 40415 THB. Most trip arrive at Paris. There is one flight that is direct to Edinburgh. Another filghts makes me go to Netherland first.

Emirates:

• The flight will arrive at Glasgow at noon. I think that is not convenience to travel from Glasgow to Edinburgh with my bulks.

In summary, it is quite sure that I have to pay around 3x,xxx to 4x,xxx for the flight. I have to find more if I can save the cost using the student document.

Thai Airways:

• There is no flight to Edinburgh. (Just have only flights to London which cost 31,xxx THB already.)
  

More information:

• p' Tan suggest that I should book the flight through STA Travel because it will be easier for change the flight, if anything happens.