(CNN) Officials at the White House's Office of Management and Budget were laying the groundwork to freeze military aid to Ukraine the night before President Donald Trump's controversial phone call with the Ukrainian President , newly released, heavily redacted emails show.

On the evening of July 24, the night before the call, OMB officials shared a "Ukraine Prep Memo" with Michael Duffey -- the office's associate director of national security programs, a political appointee and the budget official who would play a direct role in carrying out Trump's funding freeze.

"We will be standing by to answer any questions that you have and are happy to schedule time to discuss if you like," OMB official Paul Denaro wrote to Duffey that evening.

The contents of the Ukraine memo are redacted, as are many other parts of most of the emails released publicly early Wednesday morning.

The disclosure of the flurry of emails came just before midnight Tuesday, when the Office of Management and Budget gave the transparency group American Oversight nearly 200 pages of records related to the Trump administration's handling of aid to Ukraine.

The documents depict the back-and-forth at OMB and with the Department of Defense and others as the holdup on more than $200 million of congressionally appropriated military assistance to Ukraine dragged on from late summer, until around the time a whistleblower came forward in September about the President's political pressure on Ukraine. Most of the emails in the batch of records publicly released early Wednesday morning are sent to or from Duffey.

Tuesday's disclosure, part of a public records access lawsuit from American Oversight, comes as Democrats hammered the Trump administration throughout the day and night for stonewalling their subpoenas for documents related to the President's impeachment and handling of Ukraine.

This public records lawsuit, among others, has managed to pry hundreds of pages of never-before-seen potential evidence into the public eye as the Senate trial of Trump begins. Public records suits are rarely the first way Congress gains access to documents of interest for its investigations.

The Trump White House has refused to turn over documents to the House, claiming immunity from congressional subpoenas.

"The public can now see even more evidence of the President's corrupt scheme as it unfolded in real-time," said Austin Evers, executive director of American Oversight, in a statement Wednesday morning. "The volume of material released, and the volume of material still secreted away only highlights how much the administration has withheld from the House, the Senate, and the American public."

Aid discussion on July 25

That same evening of July 24, it appears the general counsel's office prepared a footnote for budget officials. The footnote is the technical device officials at the budget office used to pause the funding.

At 9 a.m. on July 25, Duffey asked career OMB official Mark Sandy about the footnote. Sandy replied that it was sent the previous night. Sandy then shares the revised footnote. Some of the correspondence is redacted, but Sandy adds: "Please copy me on the email to DOD."

The email seemed to be a reference to the next step in freezing funds: Notifying the Defense Department of the hold.

Previous troves of documents handed over by the administration revealed that on July 25, roughly 90 minutes after Trump's call with Ukrainian President Volodymyr Zelensky, Duffey notified the Pentagon that security funding for Ukraine would be frozen.

The latest emails, though, show that the paperwork to execute such a decision had already been underway at OMB in the days leading up to the call.

Lifting the hold

The lifting of the hold on September 11 was nearly as hectic, according to the email traffic in the documents.

Emails from September 11 suggest that OMB officials began the day under the belief that the freeze on Ukraine aid would continue.

"Elaine -- we are extending through thurs.," Duffey wrote to Pentagon comptroller Elaine McCusker at 3:54 a.m., an indication that the administration planned to continue extending the hold on Ukraine funds.

But as the day wore on, it appears that plans changed. By 7:30 p.m., Duffey emailed McCusker again to say, "I will be issuing an apportionment this evening to immediately release all USAI funds for obligation."

The email doesn't explain what inspired the change. By that point, news of the Ukraine aid freeze was public knowledge and Trump was facing increasing pressure from lawmakers on both sides of the aisle to release the funds. The evening of September 11, Trump spoke to Ohio Republican Sen. Rob Portman, who urged the President to release the funds for Ukraine before they disappeared entirely with the end of the fiscal year.

GOP lawmaker inquiries

The emails released Wednesday also show at least four Republican lawmakers' offices reaching out to OMB officials with questions about the unexpected holdup of US assistance for Ukraine -- all before the freeze was publicly revealed in a late August article in Politico.

The documents reveal a sternly worded email that a senior aide to Portman sent to Duffey. Portman co-chairs the Senate Ukraine Caucus, and he later helped persuade Trump to release the money in September, according to past witness testimony in the House impeachment inquiry.

Also, the chief of staff for Texas Rep. Mac Thornberry, the top Republican on the House Armed Services Committee, reached out to an OMB official on August 22 asking about the holdup in US military assistance for Ukraine.

"I heard today that OMB has put a pause on expending funds authorized for Ukrainian security assistance," Thornberry staffer Josh Martin said in the email. "Is there someone there that I can talk to to understand why?"

The email was forward up the chain to senior OMB officials, and the entire email exchange indicates that OMB received inquiries from the offices of Republican Sen. James Inhofe of Oklahoma and Republican Rep. Paul Cook of California. The documents released early Wednesday by OMB include a signed letter from Cook to acting White House chief of staff Mick Mulvaney about the freeze.

These emails are heavily redacted. It's not clear what explanation these OMB officials gave to the congressional offices.

Heavy redactions

Many of the OMB emails have large sections redacted, such as where OMB officials detail "agreed TPs," or talking points, and throughout the bodies of emails between OMB officials about the aid.

One exchange, for instance, on September 12, the day after the hold was lifted, shows OMB officials replying to emails with the subject line "QUICK REVIEW," but the rest of the words in the subject line are blacked out, because the administration claims those words are protected under deliberative process confidentiality.