Yes. I’m working on game with dynamic lights only (large open world) but I did few tests and it need always some time even for small map. In other engine I build maps relative small and build time 4-6 hours was normal even if textures was much lower resolution and map size was limited. However you should read more about level optimization for build, because some faults can make build time much longer. And many features not worth to use, because are barelly visible in game but can make build time much longer. In short words - 1. build can take very long time even on good specs. 2. read and check tutorials how to optimize level for build. 3. decide - you need baked light or not.