Investors in the US Solar Fund (USF ) must sign off a new investment policy if they want Amber Infrastructure to be appointed the new manager. 

In a stock exchange statement published on Tuesday, the board of the £150m investment trust, which has undergone a year-long strategic review, announced proposals to widen its remit. 

Changes would allow the trust to invest up to 15% in late-stage development assets that have planning and grid connection, invest up to 10% in other trusts, and remove the minimum power purchase agreement contract length, currently 10 years.

The board chaired by Gill Nott said the appointment of Amber Infrastructure as the new manager was conditional on shareholders approving the change. The group, which manages the £2.2bn infrastructure company International Public Partnerships (INPP ), intends to buy five million shares to align with shareholders.

Approval of the proposals would also allow the board to use some excess cash to repay debt. This would leave $18m (£14.8m), which could be repaid to shareholders. 

However, the amount available to distribute is not fully clear and will be determined by the final transaction costs of repaying debt and planned tax equity repayments, Numis analyst Colette Ord said.

Investors, the largest of which is Liontrust with an 11% stake, will vote on the investment amendments at the annual general meeting on 17 November in London. 

‘Given the listed fund and infrastructure experience of Amber, we would be optimistic its appointment will result in at least improved disclosure and the potential for the portfolio mix to be improved over time, given its origination track record,’ Ord said.

If shareholders do not approve the policy changes, Amber will not be appointed and the board will continue considering other proposals for the future of the 10%-yielder. However, there is no guarantee that such proposals would deliver a better outcome for shareholders, Ord added.

Peel Hunt analyst Markuz Jaffe said it was ‘somewhat disappointing’ that after more than a year of efforts, the company had failed to solicit a bid worthy of presenting to shareholders publicly, and he questioned whether there was further valuation downside risk to come beyond that already reflected in the company’s interim results to 30 June.

He added that it was unclear whether the board intends for USF to continue as an ongoing strategy under Amber’s management or if the appointment of Amber is to oversee an orderly disposal of the portfolio and the eventual return of capital to shareholders.

‘We would anticipate at least some level of pushback from shareholders if the former,’ he said.

The shares slumped 4% to 53 cents on Tuesday, a 38% discount to the June net asset value of 85.5 cents per share, and slipped a further 3.8% to 51 cents today.