era cuestión de tiempo

it was only a matter of time

→ ser
phrase Rare #42,462
it was only a matter of time Often followed by que and a verb in the subjunctive when stating what was expected to happen. Solo or sólo may be added for emphasis.
SP: Era cuestión de tiempo que descubrieran la verdad.
EN: It was only a matter of time before they discovered the truth.

Era cuestión de tiempo que encontraran a Stacks.

It was only a matter of time before they found Stacks.

— Uno de los nuestros (1990)

Solo era cuestión de tiempo.

It was only a matter of time.

— El chico y la garza (2023)

Era cuestión de tiempo que el gobierno hiciese algo sobre la contaminación.

It was only a matter of time before the government did something about pollution.

Era cuestión de tiempo.

It was a matter of time.

— Zeta (2026)

Sólo era cuestión de tiempo, y no mucho.

It was only a matter of time, and not much time at that.

— Perdición (1944)