by which conditions will a wireless logger change the gateway to another?

The conditions for changing gateway:

• The assigned gateway missed one (single) expected communication, but connection is available with another gateway.
• The connection to another gateway is 15dB better than the assigned gateway, when the signal is better than -80dB
• The connection to another gateway is 10dB better than the assigned gateway, when the signal is worse than -80dB

by which conditions will a wireless logger change the gateway to another?