I have two AMS-HT’s that I typically load with the same filament, and use one as the auto refill backup to the first one.
It would be nice to have an option that would allow me to dry the refill spool while it waits to be needed. Currently, although the refill AMS-HT looks “idle” it cannot be set to dry while it is in “refill” mode.
When the first AMS-HT runs out, and the second AMS-HT is called into service, the drying would be stopped (if it is stilling drying). This is similar to how the drying mode is stopped when a print is started.
But you will suffer a humongous delay in your approach depending of what filaments you are using. As an example you can’t use the AMS HT right after it have dried PLA since the filament path is hotter than allowed for PLA. It might work for some engineering filaments but as a general rule it will not work.
I suppose the software should wait for the system to cool as appropriate. I am not too worried about the delay since the main purpose of the auto refill, for me, is to allow a print to continue overnight or while I’m not nearby. And this delay would only be felt once per spool printed, and then only if the drying is still running.
Try it out and you’ll see it takes more than just a couple of minutes. I usually prepare my spools in advance, and when it comes to PLA, you shouldn’t dry it while it’s loaded due to the heat issue.
With the way AMS drying is currently designed, your approach would only work for a few specific filament types.