WiFi security on/off question

If blinkup has been performed with a WiFi security password (e.g. WPA-PSK) and subsequently security is disabled in the wireless AP, the imp will not connect. Is that by design? It’s causing me some problems at the moment.

Yes that’s by design.

The network specification is the SSID and the password (otherwise, someone could “capture” all your devices by broadcasting your SSID but without a password at a stronger strength).