T-Mobile USA is one of the carriers that will be happy to see the Federal Communication Commission take on the wireline number porting interval issue (story here) at its meeting tomorrow.

For more than two years, the carrier – along with Comcast – has been among those lobbying for a shorter porting interval. Currently, the carrier advises anyone considering its @home hotspot service that porting a home number from a landline phone company to T-Mobile could take six days – or longer. In contrast, wireless-to-wireless ports are often done before a customer leaves a store.

Technically, wireline companies have four business days to complete a port, but that often turns into six or more when weekends and other issues get thrown into the equation, T-Mobile representatives say. T-Mobile and other supporters of a shorter interval are calling for wireline ports to be done in one business day.

CTIA, members of Congress, consumer groups, state public utility commissions and companies like Comcast, Sprint, AT&T and MetroPCS Communications have weighed in favor of a shorter porting interval. About the only companies not on board are ILECs, which stand to lose customers faster with a shorter interval.

In a filing with the FCC last week, T-Mobile noted that a recent voluntary next-business day porting agreement between Comcast and T-Mobile demonstrates that advances in technology have “completely undercut” any ILEC arguments that technology stands in the way of shorter ports. The majority of Comcast’s simple ports to T-Mobile are now done in one business day.

The number porting issue is probably one of the less controversial ones the Commission could consider as it awaits a hearing on the nomination of Julius Genachowski as chairman; that hearing has been postponed until after Memorial Day (story here). President Barack Obama also intends to nominate South Carolina regulator Mignon Clyburn to the FCC (story here).

The Commission now has only three seats filled, with Michael Copps as acting chairman, joined by commissioners Jonathan Adelstein and Robert McDowell.