When I try to load this map, it gives me the following error and then nothing happens (the map doesn't load):

CModelLoader::Map_IsValid: Map 'C:\Program Files (x86)\Steam\steamapps\workshop\content\440\510079392\devtest.bsp' bsp version 21, expecting 20

I know this is old, but I don't know if this is just from my end or is because of a recent TF2 update or something.