Cameron McKenzie I don’t usually deal with real property law, however, this is my understanding from NSW law that may assist but should not be relied upon. So please correct me if incorrect.
The issue of a lapsing notice (under section 74J(1) of the Real Property Act 1900) seeks to remove caveats on title. The caveator then commences proceedings to extend the caveat.
An application to extend a caveat should be made pursuant to section 74K of the Real Property Act. The application should be commenced in the Supreme Court by summons (not statement of claim) and with a supporting affidavit.
This action seeks the court to issue an interlocutory injunction restraining the executor from dealing with the land pending the substantive trial of the caveator's claim.

The court will need to be satisfied of two things, which should be detailed in the accompanying affidavit.

Firstly there is there a serious question to be tried? This is not difficult to discharge. Essentially the caveator will need to show that it does have a prima facie claim and more precisely, a proprietary interest in the land.

Secondly, does the balance of convenience favour the caveat being extended? This will largely depend on the facts of the case, however courts will often hold that the balance of convenience favours extending the caveat.

Because of its urgent nature, you will need to file your application with the duty judge of the Supreme Court, not simply in the court registry. Accordingly, when your documents are ready, you should contact the associate to the duty judge and advise them of the urgent application and ask for a time to appear before the duty judge. Give as much warning as possible.

Initially, you should write to the other party’s solicitor advising that you will not allow the caveat to lapse. You should then try to reach agreement in respect of the caveat. You could offer that you will allow the caveat to lapse and the sale to proceed on the basis that the amount of $X is paid into court from the sale proceeds. This letter is advantageous as it indicates compliance with the practice notes, indication of an attempt to reach agreement before making the application for extension and may be valuable when determining costs.

Filing should be undertaken within 14 days of receiving the lapsing notice.

Due to the urgency, orders should be sought on short notice. A caveator applying for an extension will normally be required to give an undertaking to the court as to damages: see Rule 25.8 of the Uniform Civil Procedure Rules 2005.