If it pays all the tax on 2024 income and then does not make a distribution until 2025, that's fine. 

If it distributes 2025 income in 2025 and doesn't pass the income through to beneficiaries on a K-1, that's tax evasion. Also, a common practice among preparers who don't know any better.  

To repeat my unanswered question, what kind of estimated tax payments are they asking your client to make?  1041 or 1040?