Can you accidentally cause significant downtime by making a typo in a CNAME or A rec?


Let’s say I need to change the CNAME for my subdomain test.mysite.example. I want it to go to a load balancer endpoint aws-my-endpoint.example.

But in creating the CNAME, I type it wrong. e.g. aw-my-endpoint.example.

Since it’s possible that a client can cache DNS for up to 48hrs (despite what the TTL setting is), could this cause test.mysite.example to be down for 48hours? Even though I immediately fix the CNAME after noticing the typo?