Differences of the MUT_LOS and R_LOS alarms on OA boards of WDM devices Highlighted

On Huawei WDM devices, why some OA boards report the R_LOS alarm whereas some OA boards report the MUT_LOS alarm when they do not receive any light or the receive optical power is excessively low?
When the OA boards (such as WPA, WBA, and WLA) on 320G devices do not receive any optical signals, the R_LOS alarm is reported. When the OA boards (such as OPU, OBU, and OAU) on 1600G, 800G, and 400G devices do not receive any optical signals, the MUT_LOS alarm is reported.
The R_LOS alarm is used to indicate the loss of input optical signals on a single wavelength of a board such as OTU. The MUT_LOS alarm is used to indicate the loss of multiplexed optical signals on a board such as M40, D40, OAU, OBU, or OPU. It is inaccurate that the R_LOS alarm is reported when OA boards do not receive any optical signals. Therefore, the R_LOS alarm is canceled for new OA boards. When developing new 1600G, 800G, and 400G WDM systems, Huawei adjusts the alarm that is reported when OA boards do not receive any optical signals. To be specific, the OA boards report the MUT_LOS alarm when receiving no optical signals.