Feel free to corect me but arent reactions supposed to happen BEFORE strike even land? O_o
Some reactions are in response to something landing, and they reduce the amount of damage taken or retaliate with damage.
Uncanny Dodge is among them.
When an attacker hits you... It doesn't really specify whether before or after damage is rolled in the case of Uncanny Dodge.
Regardless, I'm trying to figure out a way to make presets work, so in this case I don't know how you'd set a preset for Uncanny Dodge that would satisfy a player other than to base the preset on damage dealt to the rogue.