OXFORD United’s season was still going when attention turned to the summer.

The U’s had one game to play, against Doncaster Rovers, but their defeat at Rotherham United on April 23 ended their Sky Bet League One promotion bid and saw the focus switch to 2022/23.

The rumour mill took no time to start whirring, but the transfer window lives by different rules. Here is the information you need to know.

When does the transfer window open?

The window for English Football League clubs is expected to run over the same dates as the Premier League and other European leagues.

This means it would open on Friday, June 10 and close on Thursday, September 1 at 11pm.

READ MORE: List of available League One players as clubs publish retained lists

What deals can be done outside the window?

Out-of-contract players can move before the window opens if there is an agreement between the two clubs.

United can still sign free agents after deadline day, like when Sam Baldock joined after this year's January window closed.

The U’s could also potentially lose players outside of the window if the buying club are in a country where the window is open, or if they are transferring to a non-league side.

Who have United been linked with?

So far, most of the rumours involving the U’s have been about players potentially moving on from the Kassam Stadium.

Reports of Bristol City’s interest in Mark Sykes are understood to be credible, with the midfielder out of contract this summer and expected to leave – although his destination remains to be seen.

Robins manager Nigel Pearson attended United’s win over MK Dons on April 19 but played down suggestions he was watching Elliott Moore, while Steve Seddon was also claimed to be on his radar.

READ MORE: Bristol City boss responds to Elliott Moore speculation

It would not be a transfer window without a Cameron Brannagan rumour and The Sun recently reported that five Sky Bet Championship clubs have enquired about the midfielder.

Meanwhile, Football Insider last week claimed that Charlton Athletic and Burton Albion were monitoring Alex Gorrin’s contract situation.

The 28-year-old’s deal expires this summer, although Karl Robinson has previously said he would be offered fresh terms after missing most of the season with an anterior cruciate ligament injury.

One player linked with a move to the Kassam Stadium is Scotland Under 21 international Ethan Erhahon.

The Scottish Daily Express says United and Portsmouth are interested in the St Mirren midfielder, who would reportedly command a six-figure fee.