"As economies pick up, so does demand. The effect on us is slightly longer lead time. Nothing is materially different now than six months ago." Reporting on shortages is tricky. When rumors begin about shortages, people over order for protection. That just makes things worse, and news stories on the subject can scare people into building more inventory. Often, that's overdone and the product market crashes a few quarters later.
Adtran made a Q3 profit of US$8 million after three quarters of disappointing sales and net losses. Sales were up 10% although still down from a year ago. It is shipping G.fast Version 2/Amendment 3 to Australia's nbn. AT&T, whose Tom Starr was a driving force behind G.fast, is only "sluggish." T has upped their fiber home to 5 million passed this year while slowing down on 5G mmWave.
Adtran and Huawei are cutting the price of 10G to little more than GPON to win sales. See GPON is Dead! Long live 10G. From Poland to Hong Kong, the low price of 10G is inspiring the switch.
Swisscom tells me they are getting similar G.fast units from Huawei and deploying across the country. G.fast speeds on short loops are going up from 500 megabits to over a gigabit.