managin transferred subscritpion

Hello 

we are CSP provider for a customer. In the past we create an azure plan and 3 subscriptions for him. After that customer has transferred other 6 subscriptions from another reseller. J have two question

1) from partner portal i'm able to see all subscriptions, but for these 6 subscription wher i try to 'Manage' them I receive a permission denied message. What customer should do? He have to add Foreign principal as owner ?

2) Why for 3 of these 6 subscription i can see PEC and for the three others no?

Thx a lot