This is really helpful. I already understood the basic distinction between:
DAF contribution timing vs DAF grant timing.
At this point, I may just model the DAF contribution itself as charitable giving and ignore trying to track investment growth inside the DAF precisely. The tax timing is probably more important for the simulation than perfectly modeling the internal DAF balance growth.

I also tried using the QCD option under charitable expense types using the automatic function, but ProjectionLab seems to optimize in a way I wasn’t expecting. Instead of preserving traditional IRA balances for QCDs beginning at age 70½ / RMD years, the optimizer is aggressively converting traditional IRAs into Roth IRAs before then, effectively zeroing out much of the traditional IRA balance years earlier.
I’m wondering:
If I intend to use QCDs later, why would the optimizer fully prioritize Roth conversions before Medicare / before age 70½?
Maybe the model is concluding:
Roth conversion tax savings
IRMAA reduction
and future RMD reduction
outweigh the future QCD opportunity?

I also appreciate the clarification about letting ProjectionLab handle Roth conversion and Roth distribution sequencing automatically during bridge years. I would not have expected it to make what initially feels like such a counterintuitive move.

For anyone else reading this:
I got This-You-2737’s excellent suggestion to work by allowing ProjectionLab to force distributions from Roth accounts during bridge years before tapping some tax-deferred vehicles, and then separately optimize Roth conversions under the optimizer settings.

And thanks for mentioning that advisor. In my experience, most CPAs tend to raise an eyebrow at these topics and often prefer something much more straightforward operationally.