"interim office" is a correct and usable phrase in written English.
It is most commonly used to refer to an office that is meant to serve as a temporary solution while a more permanent one is being prepared. For example, "The business established an interim office in another city while they were looking for a more suitable long-term location."
It was vacant when we bought it 30 years ago and it's been an interim office building.
To rush things – by setting up an interim office before thinking about its role and the composition of its directing committee (the budget responsibility committee) had been completed – is the exact opposite of this.
When Fred built Trump Village on the water, three blocks from his office, he put up a shanty on the job site as an interim office, so that he could always see what was going on rather than have to come three blocks.
A reminder of its importance came in July 2014, when Fiat announced it would relocate its corporate headquarters from nearby the Lingotto factory to an interim office in Slough, England, with plans to open a London base shortly thereafter.
When I visited its interim offices, in a town forty miles north of Raqqa, dozens of people had crowded outside the door of a senior councilman, Omar Alloush.
From 1989, when he left the interim post, to 2010, the office of medical examiner was unfilled for all but five years.
The interim front office, forced to deal without prospects to offer, delivered a few spare parts to supplement the roster.
Air raids sounded in the enclave, where the Iraqi interim government offices and the US embassy are heavily guarded from the insurgents.
Arrangements might be made for the first foreign troops to be in place when the Afghan interim administration takes office on Dec. 22.
The Bush administration used the law to place at least eight interim attorneys into office in 2006.
But his legal custody was transferred to the Iraqis on July 1st, a few days after Iraq's interim government took office.
