LeesSummit702

The eight current GMRS channels can handle eight simultaneous conversations today (in the same area).  The proposal below would allow for 32 simultaneous conversations without expanding the GMRS service.
For those not familiar with DMR technology, each DMR repeater signal has two "timeslots" which allows for two independent talk channels.  Two DMR signals can fit within the same space as one analog FM signal today.  This is possible because a DMR signal only requires about 7.6 kHz of spectrum, while todays wideband analog signals need 20 kHz of spectrum.
Thus, four conversations can be supported within each of the current GMRS channels. 
The center frequency of each DMR repeater (and the radios it supports) would be programmed 5 kHz above or below the current center channel.   +/-12.5 kHz might also be used.   
Below shows how this would work in reality. 

The FCC would not need to allocate new radio spectrum.  They only have to allow more efficient use of what we already have.
The other benefit of DMR is that two different repeater groups could invest in one DMR repeater, which splits the cost in two while each maintains their own "channel".   As a DMR repeater takes the same rack space as an analog repeater and only requires one antenna, the repeater site lease costs could be split between the two groups as well.
It would take the FCC some time to accomplish this, so if they started now, they might be able to complete this rule change in 2024.