Zakat on crypto - which time of day to calculate from?

Assalamo aleikum, dear mufti

I pray that you are well inshAllah.

I have a big basket of different cryptos also and I am now calculating my zakat on it. The issue I have is that the value of my crypto assets has changed a lot during the day, due to the volatile nature of crypto. So is it ok to take the lowest total value it was today and calculate zakat on that, or do I calculate on the value right before maghrib today? Can I choose what to calculate from? It has swung 30.000 usd in total value within today, my zakah day. Do I have to pay my zakat in crypto donations (2,5 % of each and every crypto in the basket), or can I calculate and pay with the money from my bank account, if I don’t want to sell the crypto right now?

I hope you take your time to answer this and update the answer in the article of yours on zakat on cryptocurrencies.