You can check your e-file status to see the date your Colorado return was transmitted There will be two entries--one for federal and one f\or your state. Please see this TurboTax Help article for instructions: How do I check my e-file status?
Has Colorado yet confirmed their receipt of my 2020 tax return?
See this for checking the status of an e-filed tax return - https://ttlc.intuit.com/community/return-status/help/how-do-i-check-my-e-file-status/00/25538
Would you check to see if my Colorado tax return has been received and accepted by the Colorado Dept of Revenue? It was supposedly transmitted to them on March 7, but it still doesn't show that Colorado received it.