Knight's Watch, Buff Mastery, and Buff Duration Increase

In what order do these stack?
Buff Mastery increases buff duration by 50%, so with that Knight's Watch lasts 135 seconds, but without it's 90 seconds.
So for example, with an A-Grade Mechanic card (10% buff duration increase) would it increase it by 13.5 seconds or 9 seconds?

Buff mastery is additive on itself like all stats. You would have 144 sec watch aka +9 seconds.

Buff mastery is additive on itself like all stats. You would have 144 sec watch aka +9 seconds.

For curiosity's sake, does the game round up at 0.5 and up or is everything rounded down. My example for relevance is Soul Contract and a Rank B Mechanic.

For curiosity's sake, does the game round up at 0.5 and up or is everything rounded down. My example for relevance is Soul Contract and a Rank B Mechanic.

I believe it rounds up.

I believe it rounds up.

I would be very surprised by this. Most things in Maple get floored

I would be very surprised by this. Most things in Maple get floored

I find range usually gets rounded up.

For curiosity's sake, does the game round up at 0.5 and up or is everything rounded down. My example for relevance is Soul Contract and a Rank B Mechanic.

I haven't gotten a fully accurate timer of knights watch with my phone, but i'm inclined to believe it rounds up.