By Nikhila Natarajan New York, Oct 4 : The timeline simply doesn't add up. Exclamation marks are flying thick and fast around two competing versions of Donald Trump's Covid-19 diagnosis timeline after White House doctor Sean Conley let slip a crucial detail on Saturday afternoon: "Just 72 hours into the diagnosis now..." If that version is correct, it means Trump was Covid positive on Wednesday morning (September 30). Here's the thing: Americans were informed of Trump's illness only after midnight on Thursday (October 1). At 12:54 a.m. on October 2, Trump tweeted that he and the First Lady Melania Trump had tested positive. This is swiftly becoming the 'who knew what and when did they know it?' story in parallel with being the political bombshell that it already is. All of Trump's engagements between the hours of Wednesday morning and Friday night are now under intense scrutiny because of the timeline mismatch between Trump and Conley's versions. Shortly before noon on Saturday, Conley delivered a sunny, upbeat report on Trump's health, saying he's "doing very well", "not on supplemental oxygen right now" and has been "fever free" for the last 24 hours. Minutes after that briefing, a person familiar with Trump's medical condition informed a White House pool reporter that Trump needed supplemental oxygen at the White House on Friday before he was hospitalised. A White House chopper transported Trump to the Walter Reed National Military Medical Center on Friday evening. Trump's doctors did not confirm if the President had been on oxygen following his Covid-19 diagnosis. They only said that Trump was not on oxygen "at this moment" in the hospital. Conley reported that the hospital plans to complete a five-day treatment course for remdesivir. Trump has already got the first dose. The "big plan for today" is for Trump to "eat, drink and stay hydrated". Conley said that Trump was brought into the Walter Reed hospital "as a precautionary measure" so that he could get "state-of-the-art monitoring". "At this time, the team and I are extremely happy with the progress the President has made since Thursday. He had mild cough and some nasal congestion and fatigue, all of which are now resolving and improving," Conley said. Trump's cardiac function, kidney function and liver function are all "normal", his medical team at the Walter Reed said. "And the President this morning is not on oxygen, not having difficulty breathing or walking around the White House medical unit upstairs," it said. Conley said Trump's blood oxygen level is 96 per cent, which is in the normal range. Trump has been treated with two experimental drugs, given intravenously. On Friday, Trump received a single dose of a drug made by Regeneron Pharmaceuticals Inc, which helps turbocharge the system with antibodies to help the immune system fight back. On Friday night, Trump was put on a five-day course of remdesivir, a Gilead Sciences drug that has been found to help shorten the course of Covid treatment. "We're maximising all the aspects of his care, attacking the virus in multiple ways. I didn't want to hold anything back, if there was any possibility it would add value to his care," Conley said. Meanwhile, Trump's Twitter thumb is back in the zone. Shortly after Conley's briefing, Trump tweeted: "Nurses and ALL at the GREAT Walter Reed Medical Center, and others from likewise incredible institutions who have joined them, are AMAZING!!! Tremendous progress has been made over the last 6 months in fighting this PLAGUE. With their help, I am feeling well!" As on date, three Republican Senators -- Ron Johnson, Mike Lee of Utah and Thom Tillis of North Carolina -- have tested positive for coronavirus. /IANS