Hi,

I can't see "Require TLS 1.1 or higher for HTTPS connections" under Critical Update column. I am using free developer salesforce product. 
My product is not able to integrate with SF because of the error

"
UNSUPPORTED_CLIENT: TLS 1.0 has been disabled in this organization. Please use TLS 1.1 or higher when connecting to Salesforce using https."

When I googled it I found the resolution but that option is not availible under Critical Update setting. 

Can anyine help?