LUBA 1 AWD 5000 - No automatic roaming between Unify Access Points?

Hi everyone - I' m happy owner of a Luba1 5000, and I've noticed that its Wi-Fi doesn't automatically switch to nearby access points with stronger signals. The Luba is docked near an access point in the backyard, but when it mows it will remain connected to that single access point, even when it is next to the house or in the front yard where other access points with much higher signal/coverage are available. Resulting in a low Wi-Fi signal. Has anyone else encountered this issue, or does anyone have suggestions for resolving it?