Nine years after Earthlink began promoting its $29.99 six-month offer for alternative broadband service for Time Warner Cable customers, the completion of Charter Communication’s takeover of Time Warner Cable has eliminated a clever way for customers to get broadband rate relief.

For almost a decade, savvy broadband-only Time Warner Cable customers have been able to bounce between new customer promotions at Time Warner Cable and Earthlink. When a year-long promotion with Time Warner Cable ended, a customer could switch seamlessly to Earthlink for six months and pay just $29.99 a month — charged to their Time Warner Cable bill. When the Earthlink promotion ended, customers were entitled to enroll as a new Time Warner Cable broadband customer and pay a lower rate for up to one year. After that, back to Earthlink.

No more.

Charter Communications closed that loophole this month and now prohibits existing Charter/Spectrum customers from getting promotional rates from Earthlink.

Once Charter customers end a broadband-only new customer promotion, currently $44.95 a month for one year, the rate jumps to $64.99… and stays there indefinitely.

The new restrictions appear in fine print on Earthlink’s website:

Charter Communications eliminated lower-cost broadband options for its customers, but claims its single remaining advertised offer (60Mbps in non-Maxx areas, 100Mbps in former TWC Maxx cities) offers a greater value because it is faster than Time Warner Cable’s Standard Internet 15Mbps plan and ends Time Warner’s practice of charging a $10 modem rental fee.

But it also costs more than earlier promotions at Earthlink ($29.99) and Time Warner Cable ($34.95).

Charter has junked Earthlink’s former promotion for Time Warner Cable customers.

“My broadband bill is now double what it used to be because I cannot switch to a broadband promotion with Charter as my Earthlink promotion ends this month,” reports Jim Deneck, a former Time Warner Cable customer in South Carolina. “I was paying $30 a month and now Spectrum wants to charge me $65 a month. The modem fee savings is irrelevant to me because I bought my modem years ago.”

Charter/Spectrum customers hoping for a better promotion from Earthlink are now also out of luck.

“After Spectrum pricing took effect in my area, my bill went up $30 a month,” writes Stop the Cap! reader Gennifer in Maine. “I was hoping to switch back to Earthlink but after placing an order with Earthlink, a representative from Charter/Spectrum called me and denied my request. It’s false competition. Since when is it okay to sign up with one company and then get a call from another telling me I am not allowed to take my business elsewhere. It’s monopoly abuse!”

Earthlink is entirely dependent on Charter Communications allowing them to resell service over Charter’s cable lines. Earthlink has been cautious not to outcompete either Charter or its predecessor Time Warner Cable, and charges roughly the same rates as a customer would get direct from either cable operator. The only benefit of the arrangement for customers was the ability to bounce between new customer promotions to pay the new customer rate indefinitely, but Charter has made sure that practice stops.

Gennifer did manage to ultimately outwit Charter, but at the cost of time and inconvenience.

“I called Spectrum and canceled my service and we signed up as a new customer under my husband’s name,” Gennifer writes. “Unfortunately, Charter won’t process an order at an address with existing service so you have to cancel and turn in equipment first and then place an order under a different name to qualify for a promotion. They really don’t want to give their customers a break or a discount. I wish we had other options.”