"immediately once" is a correct and usable phrase in written English.
It is generally used to mean "the moment something happens". For example, "I will call you immediately once I finish my shift."
"We can tap into it immediately once there is a shortfall".
"I remorsefully removed it immediately once I became aware that it is inappropriate and offensive".
"You notice them immediately once you get into space," Chiao says.
"Immediately, once he got into the studio, I could see how cathartic it was for him," Ms. Krauss said.
More immediately, once the vote is held, the question is: Will it be accepted by winners and losers alike?
He stood throughout, then left immediately, once Monica Bellucci had had the beauty beaten out of her.
"He's going to lose half or more of women immediately once they find out what that would do to birth control".
"I reached out to the family immediately once the article came out, and I had a really productive, sincere conversation with the mother and the daughter.
"He's going to lose half or more of women immediately once they find out what that would do to birth control," Downing told me.
The Buffalo Bills and Mario Williams The Buffalo Bills' interest in Mario Williams, who visited Buffalo immediately once free agency opened, couldn't make any more sense.
A user could also buy a CD from an online retailer and listen to it immediately once MP3.com had confirmed the transaction.
