sbh = Scheduled block hour.
EG. Stansted to Tenerife (sake of argument) is 4 hours there and 4 hours back.
So thats 2x4 block hours. Your SBH for that day is 8 hours.
This does not include the 45mins before departure when you are due in crew room. It does not include turn arounds. It does not include delays etc.
This is what you are paid from.
So that day is 8 SBH and you get exactly that even if the wind is
and it takes 5 hours down and 4 hours back, 45min turnaround, and a 1 hour slot. Could end up very easily doing an 11.5 hour duty day for 8 hours pay. Such is the nature of the beast when dealing with SBH pay.