Andy Hessenthaler has become the first manager to depart an EFL club this season, after just five months in charge.
The O's have suffered back-to-back defeats and are 14th in Sky Bet League Two.Hessenthaler took charge of the O's final five games of last term before being given a one-year deal in the summer, but departs after three wins in their nine league games of 2016/17.
Here's the updated EFL managers table, ordered by date of appointment:
| Rank | Manager | Club | Appointed | Division |
| 1 | Paul Tisdale | Exeter City | 06/06 | League Two |
| 2 | Karl Robinson | Milton Keynes Dons | 05/10 | League One
|
| 3 | Paul Hurst
| Grimsby Town
| 03/11 | League Two
|
| 4 | Jim Bentley
| Morecambe
| 05/11 | League Two
|
| 5 | Steve Davis | Crewe Alexandra | 11/11 | League Two
|
| 6 | Gareth Ainsworth
| Wycombe Wanderers
| 09/12 | League Two
|
| 7 | Neal Ardley
| AFC Wimbledon
| 10/12 | League One
|
| 8 | Mick McCarthy
| Ipswich Town
| 11/12 | Championship
|
| 9 | Keith Hill
| Rochdale
| 01/13 | League One
|
| 10 | Simon Grayson
| Preston North End
| 02/13 | Championship |
| 11 | Phil Brown
| Southend United
| 03/13 | League One
|
| 12 | David Flitcroft
| Bury
| 12/13 | League One
|
| 13 | Martin Allen
| Barnet
| 03/14 | League Two
|
| 14 | Darrell Clarke
| Bristol Rovers
| 03/14 | League One
|
| 15 | Micky Mellon
| Shrewsbury Town
| 05/14 | League One
|
| 16 | Michael Appleton
| Oxford United
| 07/14 | League One
|
| 17 | John Coleman
| Accrington Stanley
| 09/14 | League Two
|
| 18 | Keith Curle
| Carlisle United
| 09/14 | League Two
|
| 19
| Gary Rowett
| Birmingham City
| 10/14 | Championship
|
| 20 | Adam Murray
| Mansfield Town
| 11/14 | League Two
|
| 21 | Chris Hughton
| Brighton & Hove Albion
| 12/14 | Championship
|
| 22 | Alex Neil
| Norwich City
| 01/15 | Championship
|
| 23 | Justin Edinburgh
| Gillingham
| 02/15
| League One
|
| 24 | Tony Mowbray
| Coventry City
| 03/15 | League One
|
| 25 | Neil Harris
| Millwall
| 03/15 | League One
|
| 26 | Gary Johnson
| Cheltenham Town
| 03/15
| League Two
|
| 27 | Gary Caldwell
| Wigan Athletic
| 04/15 | Championship
|
| 28 | Paul Cook
| Portsmouth
| 05/15 | League Two
|
| 29
| Derek Adams
| Plymouth Argyle
| 06/15
| League Two
|
| 30 | Carlos Carvalhal
| Sheffield Wednesday
| 06/15 | Championship
|
| 31 | Darren Ferguson
| Doncaster Rovers
| 10/15 | League Two
|
| 32 | David Wagner
| Huddersfield Town
| 11/15 | Championship
|
| 33 | Shaun Derry
| Cambridge United
| 11/15 | League Two
|
| 34 | Dean Smith
| Brentford
| 11/15 | Championship |
| 35 | Darren Way
| Yeovil Town
| 12/15 | League Two
|
| 36 | Jimmy Floyd Hasselbaink
| Queens Park Rangers
| 12/15 | Championship |
| 37 | Nigel Clough
| Burton Albion
| 12/15 | Championship |
| 38 | Danny Wilson
| Chesterfield
| 12/15 | League One
|
| 39
| Slavisa Jokanovic
| Fulham
| 12/15 | Championship
|
| 40 | Luke Williams
| Swindon Town
| 12/15 | League One
|
| 41 | Nathan Jones
| Luton Town
| 01/16 | League Two
|
| 42 | Warren Feeney
| Newport County | 01/16 | League Two
|
| 43 | Darren Sarll
| Stevenage
| 02/16 | League Two
|
| 44 | Lee Johnson
| Bristol City
| 02/16 | Championship
|
| 45 | Paul Heckingbottom
| Barnsley
| 02/16 | Championship
|
| 46 | Craig Hignett
| Hartlepool United
| 02/16 | League Two
|
| 47 | Jon Whitney
| Walsall
| 03/16
| League One
|
| 48 | Rafael Benitez
| Newcastle United
| 03/16
| Championship
|
| 49
| Graham Alexander
| Scunthorpe United
| 03/16
| League One
|
| 50
| Grant McCann
| Peterborough United
| 04/16
| League One
|
| 51 | Dermot Drummy
| Crawley Town
| 04/16
| League Two
|
| 52 | John McGreal
| Colchester United
| 05/16
| League Two
|
| 53 | Chris Wilder
| Sheffield United
| 05/16
| League One
|
| 54 | Paul Trollope
| Cardiff City
| 05/16
| Championship
|
| 55 | Rob Page
| Northampton Town
| 05/16
| League One
|
| 56 | John Sheridan
| Notts County
| 05/16
| League Two
|
| 57 | Nigel Pearson
| Derby County
| 05/16
| Championship
|
| 58
| Alan Stubbs
| Rotherham United
| 06/16 | Championship |
| 59
| Gary Bowyer
| Blackpool
| 06/16 | League Two
|
| 60 | Garry Monk
| Leeds United
| 06/16
| Championship
|
| 61 | Owen Coyle
| Blackburn Rovers
| 06/16
| Championship |
| 62 | Roberto Di Matteo
| Aston Villa
| 06/16
| Championship
|
| 63 | Russell Slade
| Charlton Athletic
| 06/16
| League One
|
| 64 | Phil Parkinson
| Bolton Wanderers
| 06/16
| League One
|
| 65 | Jaap Stam
| Reading
| 06/16
| Championship |
| 66 | Stuart McCall
| Bradford City
| 06/16
| League One
|
| 67 | Bruno Ribeiro
| Port Vale
| 06/16
| League One
|
| 68
| Philippe Montanier
| Nottingham Forest
| 06/16
| Championship |
| 69
| Steve Robinson
| Oldham Athletic
| 07/16
| League One
|
| 70
| Walter Zenga
| Wolverhampton Wanderers
| 07/16 | Championship |
| 71 | Uwe Rosler
| Fleetwood Town
| 07/16
| League One
|
| 72
| Vacant
| Leyton Orient
| TBC
| League Two
|