AA has clamped a three segment limit for USA-Canada awards and a four segment limit on international awards if they are "
intended" (not if aa.com or the CSR gives you a routing with more segments than you presumably want) effective immediately.
No discussion of Mexico or Caribbean awards - e.g. do 500 mile upgrade limitations apply to delineate the 3 vs 4 max segments? We'll have to find out as we go along.
From Lucky at One Mile at a Time (
link)
You have to intend (my emphasis) to take the most direct routing, which is explained in the rules as follows: “The number of awards assessed should be determined by the customer’s intentions. If the indirect routing is booked at the customer’s request, multiple awards should apply using Pricing Override Options – Force Fare Breakpoint. If the routing is booked based on lack of award availability on direct routes, then an exception may be made, allowing Sabre to price as one award.”
More at OMAAT.