Why does the level of discount vary from resource to resource?
TES are funding a 15% discount on all premium resources and 30% on all bundles. Additionally, some authors are discounting their own resources, so some may be up to 40% off.
Why are some resources not discounted?
There is a slight delay on the discount being applied to newly published resources, and some authors may have decided to exclude theirs from the End of Season Sale too.