As per Platinum membership guide and website info,

100% Mileage Bonus
Your miles add up twice as fast since you’ll receive a 100%
mileage bonus on the base or guaranteed minimum miles for
eligible flights on American Airlines, American Eagle,
AmericanConnection and select airline partners. For complete
details please visit aa.com/elitestatusbonus.

aa.com/elitestatusbonus

As an elite-status member you earn an elite status mileage bonus on the base or guaranteed minimum miles for each eligible flight on the carriers listed below:
* American Airlines (including codeshare flights booked as an AA flight number)
* American Eagle®
* AmericanConnection®
* Alaska Airlines
* Cathay Pacific Airways
* Dragonair (Effective November 1, 2007)
* Finnair
* Iberia
* LAN 1
* Qantas Airways
* Royal Jordanian Airlines

Elite Level Elite Status Bonus
AAdvantage Executive Platinum® 100%
AAdvantage Platinum® 100%
AAdvantage Gold® 25%

I think it shoube be qualify for remain elite status when I reach AA Platinum, right?

(Sorry, my mistake and mis-understanding. Someone already explained for me, thanks!)
(I thought that means 100% Bonus EQM for AA Plat, but it should be 100% Bouns RDM)