Extended Range ePTP options

Being a rural service provider, we have many backhaul links that are over the 15 mile maximum range for the ePTP mode in 40mhz.  We use ePTP mode for the lower latency and higher bandwidth.  

For us, it would be nice to have an "extended range" ePTP mode that would likely give up some latency to extend the TDD window, but still have the bandwidth advantages and (still) lower latency than TDD PTP mode.  

Maybe latency increases to 5ms but now 40mhz has a 20 or 25 mile range.