There is nothing wrong using the lump sum strategy if the money is there it won't trigger any financial stress if the income is available there are rich people who are using the lump sum strategy and also the DCA strategy poor people may also decide to lump sum if probably they won a lottery or unexpected huge amount of money came there way he or she may decide to lump sum without them selling there bitcoin holding since they will still be using the DCA strategy.
But it is better they use DCA than to buy at once even if the money is there. Bitcoin price always fluctuate and if we buy at once using a large money and the price is down a lot, we can be difficult to buy back Bitcoin. But if we can steady to use the same amount of money and allocate the money by our capability, that will help us to have the money and prepare for the next down time.
You sound like a trader who only want to invest for a short period of time there is nothing wrong if the have the money and decide to lump sum even if the price of bitcoin drop it will surely go up again so the up and down of bitcoin shouldn't worry you as an investor who is investing for a longer period of time 4-10 years or more, you can still lump sum and still continue with your regular DCA strategy.