Recoverable Fatal Error – Object of class WP_Post could not be converted to string

Im using ACF and trying to show a post type title based on the current time. So I have my post type entry with start_time and end_time and my conditional is showing my div.onAir, but Im getting this Recoverable Fatal Error. Here is my code:

I feel Im close, but I haven’t seen this particular error before. Any help would be appreciated! Thanks.

UPDATE:

Tom changed my code up to use WP_Query. I had an issue with the timestamps in ACF and WP matching up. Once I figured that out, this code renders the correct comparison of show posts that I was going for. Please note that I used date_i18n('g:i a'); which fixed my localization timestamp. Thanks Tom and Yuri!