Ms Arlene Foster, an honorary secretary of the UUP who yesterday withdrew her resignation from the party officers' group,will attend tomorrow night's meeting of the 14-member body.
The Rev Martin Smyth will chair the meeting which will discuss Monday's High Court ruling against the decision to suspend Ms Foster, Mr Smyth and Mr Jeffrey Donaldson. They are also expected to discuss Mr Trimble's victory in a no-confidence vote in his Upper Bann constituency on Tuesday and the fact that 37.5 per cent of his constituency association did not support him.
Critics of the UUP leader, Mr Trimble, are buoyed up by Mr Justice Girvan's damning ruling that moves inspired by Mr Trimble to suspend the three MPs were improper. He awarded costs of up to £25,000 against the party.
Ms Foster had stormed out of the last officers' meeting on June 26th when disciplinary moves were initiated, claiming the party leader was behaving in a vindictive fashion. She said yesterday that her resignation, offered to Mr Smyth, had not been accepted and she had reconsidered. Mr Smyth said: "She tendered her resignation as an officer on the basis that she did not wish to be part of an officer team pursuing an action through a process which she believed to be unjust and ill-conceived. Now the High Court has vindicated that stance and that particular disciplinary process has been forced to cease."
Mr Trimble has echoed remarks made by the party chairman, Mr Jim Cooper, that the leadership of the UUP should take time to consider Monday's High Court decision and what he called "the whole matter" at issue within the party.
Mr Trimble's Assembly colleague in Upper Bann, Mr George Savage, has been a firm ally of the party leader. However, he has declined to state if he supported Mr Trimble at the no-confidence debate on Tuesday in Craigavon. The scale of the No vote in Upper Bann and the reticence of Trimble loyalists to voice outright support for him illustrate the party leader's uneasy position.
Unionist sources make no secret of the seriousness of the continuing threats to Mr Trimble's leadership and one elected representative has spoken to The Irish Times of the need for a change at the top, perhaps even an interim leader, to put the party's serious divisions behind it.
Mr Trimble is anxious to divert attention to matters he deems more important such as the need for a definitive end to all alleged paramilitary activity - the cause of the suspension of the Stormont institutions last October.
He was in Westminster yesterday for discussions on the proposed new EU constitution. Speaking after the no-confidence vote on Tuesday, Mr Trimble said the issue was of the utmost importance for Northern Ireland.