What information?
4L is Amex platinum travel specific benefit.
3x is amex reward multiplier benefit and depends on amex card it varies and this portal is for "all amex cards", not only limited to platinum travel.
Both are separate. If you want you can combine, like 4L on amex reward multiplier will provide 3x reward points + milestone benefits.
Amex reward multiplier has separate restrictions like amzn pay voucher limited to 10k per month, fk limited to x amount per month like that. This applicable for all AMEX cards, not only specific to platinum travel.
This is accelarated service similar to HDFC SmartBuy. Where even if you spend 1Cr. you still eligible to use smartbuy for upto 5x or 5% rewards.
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after 4L platinum travel doesn't end, you can still get 1x rewards but there are no further milestone benefits.