The EFL have confirmed the deadlines for the 2019 summer transfer window.
The revised approach will mean split deadlines for clubs in the Championship, and those in League One and League Two.
At the start of the 2019/20 campaign, Championship clubs will have until 5pm on the Thursday, August 8 (the weekend before the start of the Premier League season) to complete all incoming permanent and loan registrations.
It is a change to the previous regime which allowed all EFL clubs to sign players on loan until the end of August, while permanent deals couldn't be completed after August 8.
That allowed Sunderland to sign midfielder Max Power on loan at the end of the month after a permanent deal fell through.
The new rule, which has been backed by EFL clubs, will allow League One and Two clubs to complete permanent and loan signings until the end of August.
With August 31 falling on a Saturday in 2019, League One and League Two Clubs will have until 5pm on Monday September 2 to sign players this summer.
The new rule means if Sunderland win promotion from League One via the play-offs, the Black Cats will have just 74 days to complete their summer business as a Championship club.
If the Black Cats overcome Portsmouth in the League One play-off semi-final, they will progress to a Wembley final on Sunday May 26.
Key summer transfer window dates
Thursday May 16 - Domestic transfer window opens in England
Sunday June 9 - International window opens
Thursday August 8 - Transfer window closes for Championship clubs at 5pm - permanent and loan signings
Monday 2 September - Transfer window closes for League One and League Two clubs at 5pm - permanent and loan signings