The move aims to bring an end to conflicts between True Move and its concession provider CAT Telecom and a similar dispute between Digital Phone Co (DPC), a unit of mobile leader Advanced Info Service (AIS), and CAT Telecom.
CAT Telecom wanted True Move and DPC to continue paying it 30% of their total revenue from retaining their customers who are still using 2G mobile networks on the 1800-megahertz spectrum under concession agreements that expired last September.
But the two operators refused to pay what they called "too hefty rates" as the company is facing accumulated losses of 3 billion baht due to the regulation that it retains its existing 2G customers for another year after its concession expired.
True Move claimed its revenue from the 2G service declined sharply to 500 million baht per month, compared with 1.5 billion baht a month before the expiry of the concession.
True Move still has 4 million customers on the 1800-MHz spectrum, down from 17 million last October. DPC has 4,000 users, down from 70,000.
The National Broadcasting and Telecommunications Commission (NBTC) ordered True Move and DPC to retain their customers for another year after their concessions expired, but they are not allowed to acquire new subscribers under the current overseeing regulation.
Col Settapong Malisuwan, vice-chairman of the NBTC, said a panel is changing some conditions in the regulation in order to end the dispute and pave the way for a 4G auction scheduled for next year.
"The panel expects to submit a revised draft amendment to the regulation next month," he said.
The NBTC initially planned to auction off the 1800-MHz spectrum, previously operated by True Move and DPC, for 4G service this month.
But the junta in July ordered the NBTC to suspend the 4G auction for one year, as it wanted the regulator to amend several impractical sections of the Frequency Allocation Act before any auction takes place.
Korkij Darnchaivijit, the NBTC's vice secretary-general, said the panel was also considering letting mobile operators use the 1800-MHz spectrum for one year to relieve congested mobile data traffic. Operators might be allowed to temporarily provide 3G or 4G wireless broadband services until next July to ease poor mobile signal quality.
Mr Korkij said the NBTC was mulling whether to allow True Move and DPC to seek new customers during the overseeing period, but both companies would have to pass on all profits to state coffers.