It's about time!

(it's) (a)bout time

An expression used to emphasize that something should have occurred a long time ago. Well, about time you got here—I've been waiting for over an hour! It's about time that high schools taught their students about basic banking and finance. A: "Tom finally moved out of his parents' house." B: "Bout time! He's 40 years old."
See also: time
Farlex Dictionary of Idioms.

It's about time!

Inf. It is almost too late!; I've been waiting a long time! (Said with impatience.) So you finally got here! It's about time! They finally paid me my money. It's about time!
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • (it's) (a)bout time
  • about time
  • about time too
  • any time
  • anytime
  • any time means no time
  • any old time
  • at all hours
  • at all hours (of the day and night)
  • (it's) time to run
References in periodicals archive
NHS chart shows medicines no longer available on prescription It's about time! I used to work in a pharmacy and saw the ridiculous amount of prescriptions handed out for paracetamol and other cheap medications.
You say..
Fans of Williams' no-nonsense, upfront-and-open style will thoroughly enjoy It's About Time! A booklet of the complete lyrics to all songs is included with the physical CD version of It's About Time.
It's About Time
There's been a great deal of talk of late (and it's about time!) about the nursing shortage--how young people are seeing the terrible pressures nurses work under in this managed care era and are saying "no thank you," and how the existing nursing force is shrinking by attrition.
The Administrator: An Endangered Species