Question about DAL: do any of you other DAL regulars know what's behind the big price increases at National in the coming weeks?

Typical market rates, weekends with no unusual discount codes, range between $18 and $22 per day for a midsize at the recognizable national agencies. National is jumping to about a 50% (!) premium above that, if not more. Alamo is not and even National's traditional competitor, Hertz, is not. This holds true on most April and May weekends.

For my next 5-6 rentals, I'm switching to Budget for the 5k HH per rental and $12.50 in "Budget Bucks" per rental. After April 30th, I'm unsure of where to rent...I guess I'll watch the Alamo, Budget, and Hertz promotions since National doesn't tend to run partner promos on 2-day rentals. I've always enjoyed National and have traditionally paid a 10-15% premium over market to rent Exec Aisle. But I won't pay 50%...I simply don't log enough miles in the cars to justify that premium.

Just wondering if there's any specific reason behind it... Maybe they're just keeping their supply tight at DAL and people really love Exec Select that much?