My guess would be that blanket discount offers from suppliers are going to happen at times when their sales are traditionally slower.
I don't have any solid data or sales figures to back this up, but my gut tells me that this time of year, with spring right around the corner, and income tax return checks coming in to folks, that this time of year is when sales at places like Jim Carters and American Classic picks back up.. people getting ready for the upcoming driving/show season.
Dosen't make much sence to offer discounts when folks are buying.. only when overall sales are sluggish.. since it's better to move product at a lower profit margin, than it is to sit on inventory.. because the electric bill, payroll, and general overhead expenses keep coming even during the lean times.
If I had to guess, i'd say you can expect somebody to step up to the plate with a discount closer twards spring.. to help increase visability and clear out inventory.