I asked ASUS about updated firmware never asked for a downgrade file but this is the response I got:
"Hello Jean Rivera-Ramos, Thank you for your patience and patronage! We would like to inform you that we no longer provide previous firmware versions or downgraded software packages on ASUS official website. This is to ensure that the security updates on your phone remain up-to-date with the latest firmware versions which will only be pushed via FOTA. We appreciate your understanding and patience.
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and while I never asked for a downgrade, their response it is concerning, as I understand they will not provide full firmware anymore for incremental updates, there has been 2 updates after the last version provided by them on official website which is WW_33.0610.2810.157, but there was WW_33.0610.2810.159 & WW_33.0610.2810.166.
@Mattias_ASUS could you provide more information on the matter? What's the point on providing Release notes here on the forums and not provide a download link for the latest firmware version on the same forum or a link to official download website , or at least a link to the incremental OTA. because according to their own response on the email, to ensure that security updates on the phone stay up to date, they know all people who decided to unlock their bootloader they can't receive OTA, but that is no excuse to provide full firmware version of such updates to ensure the security to the people that develop software and apps for their phones, it is not fair from asus to provide such updates only to people that keep their devices locked only.