digimesh network two questions about TX messages

We have a little confusion on Digimesh network
Question1
Our digimesh radio module (XB24C) is controlled by a microcontroller that communicate with module using serial port in API mode
The microcontroller transmit sequence is:
.- Send a UNICAST transmit request API frame 0x10
.- Wait until Extended Transmit Status 0x8b was received
send another transmit request if need

But if we change previous sequence with this
.- Send a UNICAST transmit request API frame 0x10
.- Send a UNICAST transmit request API frame 0x10
.- Send a UNICAST transmit request API frame 0x10
Send multiple transmit request frames without waiting for 0x8B frame result on previous transmit request.

What is the module beahvior ? (Our network is formed from 9 nodes and 3 repeaters)
A ) Buffer the subsequent transmit requests, wait until first frame arrive at destination (receive ACK) and then TX next frame
B ) transmit all frames as soon is possible without waiting the result of previous transmit frame

In case A only one frame at time can travel in the digimesh network. Obiouvsly there are no “air contention”
In case B multiple frame can travel in the network but digimesh must prevent that several modules (repeaters) transmit at the same time ? It Do this ?

Question2
Our network Endpoint is battery powered configured non routing (CE=2) and Async sleep (SM=1)
If two or more modules wake at the same time and send a transmit frame request (0x10), the digimesh network sync the module transmission preventing confilcts or the modules can transmit all toghether at the same time.
(We can use the CA parameter but suppose CA=0)