speed - What to do when it takes a long time to load the content into the app?

I'm replacing all loaders (spinners) in the app I'm working on, because I need another solution which won't be tied so much with waiting. When people see loader they're frustrating, because loader indicates that they need to wait, so instead of loader I'm going to display pre-loading skeleton screens as Luke Wróblewski recommended and as e.g. Facebook uses (print screen). A skeleton screen is essentially a blank version of a page into which information is gradually loaded. This creates the sense that things are happening immediately as information is incrementally displayed on the screen.

In this case user has a connection with network but the connection is bad e.g. 2g or the time of servers respond is longer than usual.

My question:

1. What to do when content isn't displayed for a longer time (e.g. more than 5 or 10 sec)? Whether the pre-loading skeleton screen should be displayed all the time until the content will arrive or should be replaced by something else e.g. additional information - "we're sorry that it takes so much to load the content, check your network".