a question of time

a question of time

An inevitability or eventuality; something that is or seems sure to happen at some point in the future. With your reckless spending behavior, it's just a question of time before you go broke.
See also: of, question, time
Farlex Dictionary of Idioms.

only a question of time

or

just a question of time

COMMON If something is only a question of time or just a question of time, it will certainly happen at some time. It was only a question of time before news of the argument leaked out. There are some small groups fighting in parts of the city, but it is just a question of time until order is restored. Note: People sometimes just say that something is a question of time. It's a question of time before his designs are considered classic.
See also: of, question, time
Collins COBUILD Idioms Dictionary, 3rd ed.
See also:
  • a matter of time
  • only a question of time
  • be a question of time
  • be just a question of time
  • be only a question of time
  • it's only, just, etc. a matter/a question of time
  • be only a matter of time
  • be just a matter of time
  • be all over bar the shouting
  • a matter of days, miles, pounds, etc.