Thanks thunderbug for your answer
I was asking these questions to know the criteria of choosing one or other option in the event you have to burn more fuel. I was looking for the advantages and disadvantages of each of the options. (Speedbrakes extended or Gear down)
Your comments were very helpful. Thanks
Regarding the AOA with Speedbrakes extended:
I found the following paragraph in the article “Understanding the angle of attack”
pilotlab.net/library-2/systems-performance/understanding-aoa-part1.pdf
“Wing-mounted speed brakes or spoilers have the opposite effect. They reduce the lift at a given AOA; they also reduce the maximum lift achievable but, surprisingly, increase the AOA at which stall occurs.”