Passengers were left shocked and bewildered when Metro services were suspended on November 13 after cracks were found in the trams, raising urgent safety concerns.
On December 15 the first repaired trams and a few of the brand-new CAF Urbos began running a skeleton service between Wolverhampton St George’s and Bull Street only.
But trams have not yet been able to travel between Bull Street and Library.
Earlier this month, West Midlands Metro announced passengers could look forward to a full service resuming from Sunday but that date has now been pushed back a week.
A spokesman said: “While permanent repairs to West Midlands Metro’s existing tram fleet remain on schedule and are progressing well, the commissioning of some of our new trams is taking slightly longer than anticipated.
“Our engineers are working with the manufacturer to complete this essential process as quickly as possible, but we will be unable to resume services to Library on January 30. This was an estimated date for the full resumption of services.
“Subject to tram availability, we now expect a return of passenger services to Library from February 6.
"In the meantime, we would like to apologise to customers for the continued inconvenience.”