Seems to me it’s roaming between the (probably many) available APs that your hotel has available to connect to- maybe because you’re far enough away from them all it’s having a hard time keeping a good signal. Can you try moving the AR750 closer to the hallway (or maybe a window) and see if it makes any difference?
Due to the way the repeater (WISP) mode works, if the WAN WiFi roams to another AP, your computer may temporarily lose the signal until the WAN WiFi gets successfully associated (I think that’s right, @alzhao? Please correct me if I’m wrong.)