I assume that when you take leave you only need to take 5 days out of your 20 annual leave to get 5+4+3 = 12 days off.
Correct
How do bank holidays figure
They are not seen as special days (i.e. no extra day off for working on a bank holiday)
From A4
Twice a year you have a 4 week "reserve" period
The duty cycle is a 21 week block, the first 17 of which are 5-4-5-3 and the last 4 weeks are "reserve" (random-ish) roster. So within a period of 12 months, you can have 2 or 3 reserve periods (depending on the 12 months that you pick). And if you're bored at home with a sore throat, like I am, you can grab your calculator and find out that the average is 2.4 reserve periods a year
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