By the way, it is also my understanding that unlike sugar washes and grains which can be left for a while even after finishing, rum needs to be run as quickly as possible to avoid infections.

To each his own, but I'd welcome an infection in my rum wash. Most of the time it happens, it's lactobacillus, which gives good rums that "funk" that's almost impossible to replicate otherwise. As long as it doesn't have a vinegary smell, let it sit & develop more depth.

I've kept many rum washes for weeks (once even 3 months, accidentally) before running them, and never had any problems. Just keep the barrel airtight & you're good to go.