Trump is so desperate for a relief package now because he realises it hurts his reelection chances not to be.
That's to say, until the breakthrough of a selfish thought, he didn't give a damn.
Now he only wants the parts of the package that he thinks help him with getting reelected. But not the rest of the $2.3t package because he sees it as benefitting Democratic states.
He only has one prism. Reelection. Reward his voters in swing states. Damage and extort Biden's.
"The House & Senate should IMMEDIATELY Approve 25 Billion Dollars for Airline Payroll Support, & 135 Billion Dollars for Paycheck Protection Program for Small Business. Both of these will be fully paid for with unused funds from the Cares Act. Have this money. I will sign now!" - Trump tweet