Can I move in before the Fire Safety Certificate is issued?
Not lawfully, unless a Temporary Fire Permit has been issued. SCDF states that a Fire Safety Certificate is required before using or occupying premises, and that occupying without it is an offence under the Fire Safety Act 1993. A Temporary Fire Permit allows use for a limited period before the certificate, but only where fire safety works are complete with very minor outstanding issues. Plan the move date after the fire-safety step, not before it.
From the RRD Field Guide, checked against the sources cited in Commercial Fit-Out Programmes in Singapore: Realistic Timelines and Where Delays Come From. General information, not advice for your project.
The fuller picture
A Singapore office or retail fit-out runs through design, authority approvals, landlord submissions, procurement of long-lead items, site works, testing and commissioning, fire-safety certification and handover. Delays usually come from approvals, late design changes, long-lead M&E items, landlord working-hour limits and coordination. Early landlord submissions, early procurement and a baseline critical-path programme tracked weekly are the main defences.