Hi everyone! It has been tested within 4-5 month and now I'd like to claim that using Ethernet connection on AM Server's phone makes using it exactly perfect - stable, reliable, almost no connection's timeout. There were two smartphones tested as AM Server carrier Samsung S8 and Samsung S10, both over USB-C Ethernet adapter (two noname, from Ali) connected to router , showed either 10Mbs or 100Mbs speed. The same smartphones were connected over wifi to the same router in previous life. Randomly I took the log from server and calculated amount of timeouts lasting longer than 1000ms for all my 83th Am-related devices and checked AM-Remote connection . Nothing where changed in the network (except one new device appeared and one old disappeared and AM server was moved under Ethernet) . I wouldn't prevaricate that all timeouts are gone , but at least amount of timeouts cut in several folds. Sure the vast majority of devices are wifi connected( and collection their logs is practically unreal) but for those that is Ethernet connected I never saw any timeouts or connection troubles(two of them were monitored from their personal logs).
So, I can recommend using Ethernet connection for AM if you want to see your server , like real SERVER)) , especially you control something important like water, electricity , gas and etc..
Hope it'll be useful for someone.