I'm not sure it's fair to say the priciest configs ship sooner. They're really only delivering two trucks right now, the quad motor, large pack versions of the R1T and R1S. The dual motor configs are cheaper but were only introduced recently. The max pack versions have been for sale for awhile and none of have been delivered, but they're also the most expensive.

They did raise prices around 1 year ago but I've seen no evidence that they've prioritized orders for those who purchased after the price increase or who equipped more expensive options (options like tents and racks are shipping separately).