ASX-listed Bubs, one of a2 Milk's Australian peers, has been air freighting product to the formula-strapped US market for several weeks.
A2 Milk's main infant formula market is China, and analysts have debated whether the ability to send some stock to the US would be a help or a hindrance for the former high flier, whose profitability has come under pressure in recent years.
"It might be helpful in terms of them using up some of their inventory that they have built up," Harbour Asset Management portfolio manager Shane Solly said.
"You hope that it (US sales) becomes a long-term thing but in and of itself, this is a short term contract and it doesn't look long term," he said.
"If it's short term, it doesn't really move the dial," he said.
With China being a2 Milk's main market for formula, there was earnings risk associated with the company due to economic headwinds in the PRC, he added.
A2 Milk's result for the June year is expected on August 30.