50G & 100G Ethernet for Backhaul
Huawei has delivered a testable 50G unit to China Mobile and passed testing at the European Advanced Networking Test Center.
They also offer a 100 gigabit unit with four 25 gigabit devices. A 2 x 50G unit is planned that will be air-cooled.
Verizon has chosen 40 gigabit NG-PON2 for small cell backhaul, but most other carriers are choosing ten gigabits. Verizon has been testing NGPON2 from Calix and Adtran for a year and is now deploying hundreds of 5G small cells.
Softbank was startled by large signups for fixed wireless in Tokyo, a city with almost 100% coverage of fiber home. T-Mobile in Austria has also seen a trend.
AT&T is fibering 3M homes/year. Telefonica doing millions in Brazil and most of Spain. France Telecom is well along and nearly all of Portugal covered. Bell Canada recently decided to speed up fiber because cable was killing them. 
12 bonded lines of 35b VDSL should be able to deliver 2 gig downstream ~400 meters. That's comparable to the most common G.fast backhaul, 2.4 gig GPON. Telcos are confident few will use the high speeds simultaneously so the high over-subscription is realistic. Upstream on the older DSLs is lower, so the upstream will probably be limited.