S4128 - port-channel with more than 1 VLAN and VLT

Hi there,

I have this:

...

interface port-channel1

 no shutdown

 switchport mode trunk

 switchport access vlan 1

 vlt-port-channel 1

...

and I would like to add VLAN X.

Can I simple add "switchport trunk allowed vlan X" or will this interrupt my connection? I need both.

Thank you!