[3.25] ❄️ Icicle Mines Deadeye ❄️ Cheap / League Starter / Fast Mapper / 1st Day T16

Looking to play this for league 2.0, quick question regarding leveling, whats the minimum to switch to icicle mines? I see in the POB the skill switch is at level 52, is this a mandatory requirement or can you switch when you get access to minefield gem?