The observation wheel investor said holders of £1.16mln worth of convertible notes had agreed to the maturity date being pushed out until May next year and to interest being paid at maturity/conversion rather than quarterly.
Holders of another £1mln worth of convertible debt have also agreed to interest being paid on maturity /conversion.
Last week, Challenger negotiated an extended maturity date of 2 March 2018, a fixed conversion price of 12p and interest to be paid on conversion/ maturity of £500,000 of convertible debt.
Mark Gustafson, chief executive said: "We are absolutely delighted that our note holders are supportive of our restructuring efforts and the changes to these convertible notes.
"These amendments will allow us the flexibility and time to pursue additional projects over the course of 2017.
“Alongside this, we are pleased that positive progress continues to be made at the US$590mln New York Wheel Project, in which we have a US$3mln equity interest."