I have been very satisfied with this site and donation privileges however when is it that special offers are given for example 5 to 7 times bonus points to even the rare 12 but when does it happens? Thank you for the service

At what time on december do they raise the donation bonuses? is it on the last weeks?

I have been very satisfied with this site and donation privileges however when is it that special offers are given for example 5 to 7 times bonus points to even the rare 12 but when does it happens? Thank you for the service