Offering buff duration unaffected by buff expiration rate

When using runegraft of the warp, which gives 30% decreased buff expiration rate, the duration of offering buffs is unaffected. Other buffs are extended.

Testing: Stopwatch to determine length of buff. Offering lasted 7 seconds which matches the duration on tooltip.

Expected result: Buff expiration rate would increase the length of the buff to 10 seconds

Noticed the same thing, specifically when using queen's hunger chest piece which auto-triggers them. Don't know if self-casting has the same issue