Is there a order of application between fasteners or external forces in the static simulation?

In my simulation I have a difference between the measurment in reality and the deformation solution of the simulation.

Case: At the end of tube A is a clamp that uses 4 screws to clamp tube B, at both ends of tube B are forces that cause a torsion in tube A.

When calculated with bolt fasteners in static simulation the result does not compare to the test in reality when first the bolts are tightened and after the force on tube B is applied.

althought when in reallity the foce and tightening of the screws is applied step by steps (25% 50% 75% 100%), the result is the same as the simulation.

This brings me to the conclusion that the in the simulation the fasteners are applied simultaneously with the force. Is this true? if so, how can i change this?

And how can i apply different forces, within a assambly, one after a other (first 100% force X than force Y)?

thanks!