NEVER mind....found the answer.... "We recommend that blood donations be given a week apart and up to four working days before the date of your surgery. After the blood is given, it can be stored for up to 35 days."
Another limit on autologous donation is the donon's haemoglobin count. If it is too low the donation will not be taken.
I was refused for this reason prior to my surgery for heart by-pass and aortic aneurism repair and so I had to accept blood from the blood bank.
If surgery is pending, you should make your donations as early as possible within the specified time frame.
Tell your surgeon immediately if you are contemplating autologous donation.