E32 module in Power Save mode issue

Hi, maybe could provide some ideas and advice here. The project consists of two E32-868T20D modules, let's say A and B One (A) is configured as a transmitter the other one (B) as a receiver Sending datagrams from A to B looks reliable and fine as long as the are setup in Normal or Wakeup mode for both circuits regarldess the air-rate (from 300 to 19200b). Moving the receiver (B) in PowerSave mode, fixing the sender in wakeup mode with same WOR value for both, the reception on B works stable for an air rate up to 2400bauds. Setting a higher air rate involves unreliability where, sometim,e the receiver doesn't seem to get correctly the air datagram or get it but not sending it to the MCU. I check this on a scope, looking at the AUX and TX signals (Lora side chip). It confirms the AUX signal, sometime, is not activate and so data on the UART not sent. I check the same behavior when the role of the transmitter and receiver are inverted (A becomes the receiver in Powersave mode) Both modules have the same revision firmware 45 0C 14 Fixed transmission for both, FEC ON, POWER 21 The UART speed (8N1) is checked to be 2x or 4x the air-rate the two modules are very closed to each other (0.5 meter). Is it something normal " !! yes there are constraints when working in PowerSave mode and it is documented...!" May I miss something here in my datasheet module interpretation for the Wakeup/PowerSave mode couplet Thanks for your support Jean-Michel