Sdlp leader Margaret Ritchie is to face a challenge for her job - after less than 18 months in office.
The beleaguered party's deputy leader Patsy McGlone is believed to be preparing to launch a formal bid to take over from the autumn.
The Mid-Ulster Assembly member, appointed deputy at the same time as Ms Ritchie was elected leader, is expected to make his position clear in the next few weeks - well ahead of the contest in November.
Former deputy leader Alasdair McDonnell, who was defeated for the leadership by Ms Ritchie, could also be in the running.
A head of steam has been building up within the party since it lost two more Assembly seats in the May election.
Ms Ritchie has also come in for criticism over her personal style and poor media performances.
There were claims from party sources that Mr McGlone was passed over following the election when Ms Ritchie again appointed Alex Attwood an executive minister - shifting from the Department of Social Development to Environment. In response it appeared a disgruntled Mr McGlone refused the offer of becoming chairman of one of Stormont's scrutiny committees.
Behind the manoeuvring is the old urban/rural split within the party, with an unresolved internal debate over its future direction, exacerbated by a lack of organisation on the ground.
Ms Ritchie has insisted she will take on any challenge for her leadership and had confirmed her intention to stand again.
Critics had hoped she would agree to stand down allowing for a quieter and smoother transition.
Others feel she has not been given long enough to develop her own team and credentials after following in the footsteps of the huge talents and personalities of Mark Durkan, John Hume and Gerry Fitt.
The 52-year-old - the first female leader of the party - defeated long-serving deputy Mr McDonnell by a clear margin of around 35 votes in February of last year.
Ms Ritchie consolidated her early success by successfully retaining her the South Down seat at Westminster, previously held by her mentor Eddie McGrady, as well as the party's two other House of Commons places in South Belfast and Foyle.
But cracks in party ranks began to emerge within days of the May election with failed Downpatrick candidate Peter Fitzpatrick calling for Ms Ritchie to step down.