Question about mastery and rarity upgrade

[Aftershock]

i know when it goes F2P you can upgrade weapon rarity and when you upgrade a mastered weapon you keep the mastery, but my question is when you upgrade a unmastered weapon does the hidden mastery stay the same or does it change when you upgrade it?
so for example say you have a purple wolfhound and the hidden mastery roll is going to be a x0.85 reload. when you upgrade it to orange will that hidden mastery roll stay the same or change to a better reload say x0.80 or will change it to a different roll altogether?

[Etaew]

The mastery is rolled when the weapon is created, it is just hidden until you master it.

So if you have a common weapon it will have the common mastery bonus unless after you upgrade it to uncommon and reset mastery, then it will use the uncommon mastery roll list.

[GM Domitasia]

Sorry for the confusion, when you upgrade rarity your hidden mastery it will remain unchanged.