There is usually little reason to worry, even if it is a day or a few days ahead of check-in.
Most hotels are not only happy to store luggage after check out, but they are also happy to accept luggage before guests check in to their room.
It's a fact that often escapes travelers when they're adding a few days before a long stay, but aren't interested in hauling all their stuff with them. Sometimes you're only out somewhere else for a night, until the real part of the trip happens.
This is a space-dependent thing, so it may not be available everywhere (a few Airbnbs we have stayed at in the past weren't clearly set up for this), but the vast 99.9% of hostels and hotels are willing to hold luggage, even for a while. Definitely call the hotel in advance to secure the early drop off before making the trek.
(It is not entirely uncommon to see travelers leave luggage for a week or more; of course, that's territory where the hotel may actually charge for it. Still, it beats the inconvenience of lugging around a heavy rig.)
