I’ll usually do a cold pull when changing colors; tho not the long drawn out affair you’ll see if you look for the process online. This will work here too...
Get yourself a pair of pliers; any with flat-ish or finely serrated jaws that can grip the filament without cutting it.
Start a hotend preheat cycle; right around 200 degrees for PLA. SOME PLA should ooze out the end if you push in on the end of filament with the pliers. This is good.
Turn off the preheat and watch the thermometer. As it drops to 120 or so, get ready with the pliers and squeeze the lever on the extruder with your other hand; hold it so the extruder’s grip on the filament is released.
As the temp drops past 90 degrees, grab the filament with the pliers and pull; you should feel a pop as the filament releases from the inside of the nozzle.
When you pull the filament out, you should see a conical blob at the end like this pic, though hopefully not full of burnt filament.
Now you can easily do all your maintenance and not have to worry about color contamination when you load new filament.
I know this sounds like a lot of assache, but most of the assache is in the reading; once you get used to doing it, takes no time at all.
mnem