The broadband boost that Comcast announced last month — doubling speeds for most customers in Washington — is taking effect.
Speed increases “will go into effect automatically over the next few days,” the company said in a release. They are characterized as “free” because no price increases are associated with them.
Customers who can’t wait another moment can go ahead and reboot their modems to get the speed boost, the company said.
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I don't know if Comcast is rolling this out nationwide or not, but my DL speed did go from ~30Mbps to ~60Mbps (according to speedtest.net) after I power-cycled my router just now. If you're a Comcast customer and feeling adventurous, give it a try.