Sorry - it may well be common practise and that as a newbie I've just not come across this form of paypal payment...
This was the email I received from paypal...
You've received an eCheque payment. An eCheque may take 5-7 working days to clear, so you'll see the transaction status set as 'Pending'.
Here's what happens when you get paid by eCheque:
The buyer's bank gets a request to pay PayPal.
PayPal receives the funds from the buyer's bank.
PayPal will transfer the money to your PayPal account after the funds have cleared and will not be at risk of being reversed by the buyer's bank.
Your buyer has sent the payment, but we suggest you wait until the eCheque has cleared before posting the item. We'll email you as soon as the money is in your PayPal account.
We estimate the eCheque will clear between 29/06/2012-03/07/2012.
Should I get in touch with the buyer and say that as soon as the echeque has cleared I will post immediately. Or do you think they'll be expecting me to post tomorrow as as far as they are concerned they have paid?