In Australia when to log on to CPDLC?

[Bungfai]

Flying from MEL to BKK.When to log on to CPDLC before or after airborne?Thank you.

[le Pingouin]

Most seem to logon before but not all. I'd suggest do whatever you normally do.

[ollie_a]

AIP GEN 3.4.7.4.3

Aircraft departing from airports either within Australia (YBBB or YMMM FIR) or the AGGG and ANAU FIRs, requesting data link services, should logon as described below:

a. On the ground using the logon address for the FIR that the departure airport is located within; or
b. Airborne at any time after passing 10,000FT, using the logon address for the FIR in which the aircraft is currently operating.

[Bungfai]

Thank you so much. Just want to clarify so we could operate according to AIP.