Andy, the requirements are for 6 months payslips and 6 months bank statements showing the pay going into the bank.
You also need formal confirmation from your employer.
UKBA state:-
Andy, you know by now my mantra 'minimise all risks'.
I may be expressing a slightly cynical approach but personally I would include my latest P60 anyway even though the UKBA say '...if this has been issued..' despite the fact it may not be relevant to the previous 6 months.
To my mind it's not 100% clear what is meant by '...if this has been issued..'
Others may disagree, but for what it's worth that's my 2 centavos worth.
If I'm wrong and you follow my suggestion you'll still get the visa.