Risk of HELOC getting called - opinions?

[Jason Powell]

I'm toying with the idea of paying off my primary and having a large HELOC to use opportunistically, with the intent to use for flips and/or BRRR. The #1 trepidation I have is the very slim odds that the bank says "give us all the money back from the HELOC that you've drawn", or less scary but still possible, close off unused credit line that I was relying on for renovations and carrying costs.

From those of you knowledgeable on the matter, how much of a risk do you perceive this is? If you didn't have the cash to pay this off entirely if the line was called, would you feel comfortable doing this?

For added context, I'm at the stage where not blowing up my financial life is far more important to me than that trying to achieve maximum gains.