so say i make a will save and choose to add my Cha bonus to it as a immediate action using the swashbuckler's charmed life ability and then fail. if i use lessons of chaldira trait to reroll the will save, do i still get the Cha bonus to the new save?
okay cool, didn't realize it was errata'd, though i have one of those GMs that says "you need at least X to pass" when it comes to skill checks or saves, so i guess that's like knowing if i fail or not.
Your GM is giving you an advantage with this trait, but a similar situation could prevail if you were able to figure out the DC from other people passing or failing the save. What the result not yet being known means in this case is that you have made the roll but the GM has not announced whether you passed or failed. In your case, if the GM has actually told you the target number, you should decide to reroll after you have rolled the die but before announcing the known failed result, since your announcement of the result would make that result "known".