Here are list of "exceptions" to the 1-transit rule.
-BACKTRACKING IS WAIVED AND TWO TRANSITS MAY
OCCUR IN CHI WHEN TRAVEL IS VIA UA TO/FROM YYZ.
5-BACKTRACKING IS WAIVED AND TWO TRANSITS MAY
OCCUR IN THE U.S. FOR TRAVEL BETWEEN THE POINTS
IN THE U.S.A. AND POINTS IN SAN JUAN/ANCHORAGE/
GUATEMALA/EL SALVADOR/COSTA RICA/VENEZUELA/
BRAZIL/ARGENTINA/CHILE AND URUGUAY.
6-FOR ALL ORIGIN POINTS MAXIMUM OF 2 COUPONS ARE
PERMITTED ON A RT/OJ BASIS BETWEEN HNL AND KOA/
LIH/OGG VIA UA AT A CHARGE OF USD 100.00 FOR 2
COUPONS.
7-BACKTRACKING IS WAIVED AND TWO TRANSITS MAY OCCUR
IN DXB WHEN TRAVEL IS VIA EK TO/FROM DMM/RUH/JED
/MCT/DOH/KWI/AMM/BOM/DEL/MAA/COK/HYD/KHI/LHE/PEW
/ISB/DAC/MLE/CMB/CAI/KRT/MRU.
Cheers