FAQ: LiFePO4 - LiFeYPO4 cell cycle voltage levels
The LFP (LiFePO4 or LiFeYPO4) cells operate within the 2.5 V to 4.0V voltage levels. In order to extend the life-span, many users prefer to operate within narrower voltage levels - as seen from the table above.
Check also the settings for the RT-BMS as explained here.