Vast Solar Pty Limited 226 Liverpool Street Darlinghurst NSW 2010

Exhibit 10.20

Vast Solar Pty Limited
000 Xxxxxxxxx Xxxxxx
Xxxxxxxxxxxx XXX 0000

Attention: Xxxxxxxxx Xxxx

24 June 2020

Dear Xxxxxxxxx

Extension of Convertible Notes No. 3 and No. 4

As discussed, this letter confirms our agreement to extend the maturity of Convertible Notes No. 3 and No. 4 on the same terms from 31 October 2020 to 31 October 2021.

Yours faithfully

/s/ Xxxxx Xxxxxxx

Xxxxx Xxxxxxx

Director

ACCENTRAL PTY LTD

ABN: 71 053 901 518

[***]

P. [***] xxx.xxxxxx.xxx