You can do approximate math from Series C, where they raised $130M at $1.5B valuation - announced in May 2021. The ARR multiples in 2021 was 50X NTM ARR. They potentially hit $30M by end of 2021 (raised sometime late 2020/early 2021).

Now even if they grew at 40-50% YoY CAGR (which is on the bullish side) - $60M-$70M ARR, approximately giving them a 10-12x ARR multiple for NTM revenue, put them squarely in the median to high-end valuation mutiple for PLG companies growing at 30-50% YoY (https://www.meritechcapital.com/benchmarking/historical-trad...)