How to Manage Startup Windfall?

I’m expecting a windfall from an upcoming tech IPO. I run a tech startup and have been angel investing in other startups since many years. I’m a business angel in the mentioned IPO and have no lock-up period. I had liquidity events in the past but not at this size. I dont’t plan to sell at IPO nor need the cash. I believe that the company will 10-20x over the next 10-20 years and would love to hold the shares. That said, I think this is not optimal for my portfolio. Possibly even idiotic. I’m wondering what the optimal play in terms portfolio construction is.

Reading and analysing the data [0] on IPOs over that last decades suggests that I should sell all shares on a schedule, like over 18 months [1], and reinvest in new startup deals.

Who has been in a similar situation and can point me in the right direction?

I do not want to retire. I want to keep investing in startups.

[0]: https://site.warrington.ufl.edu/ritter/ipo-data/ [1]: https://blog.wealthfront.com/sell-employee-stock/