They've always allowed you. But you have to contact customer service and the current balance HAS to have an original claim code.
So I was planning on using my new amazon account to buy and refund because I rather not get my main account closed. Anyways, I deposited AGC into it and then I noticed that I actually had enough money to buy my whole setup for my computer so I decided to complain to amazon so maybe they could transfer my order over or something because my main amazon has prime membership aka 2-day shipping. Anyways, I talk to a very nice amazon rep and she said that she could send in a request to amazons "Gift Card Team" and get my agc transferred within 1-2 days. I was honestly shocked and couldn't believe it, I thought they dis-allowed this type of shit. All you need to do is know the information of the account you want to send it to (Name, Billing Address, Last 4 numbers of CC, and Email) and they didn't even make me verify with the email of my amazon account with the agc balance in it. lmao? I didn't save the chat but the rep sent me a confirmation email. Below is the proof.
This came from the amazon rep that I talked to in chat:
This came to me from the "Gift Card Escalation Team":
Successful Trades: 100+
Attempted Scams against me: 1
"Gift Card Escalation Team" I didn't know Amazon had special forces