Updating W4, anticipating a Roth Conversion this year

Hello! I'm anticipating a hefty Roth conversion this year, so have updated my W4 "Other income not from jobs" to offset the inevitable tax hit.    I see the extra withholding reflected in my bi-weekly paychecks and figure it should cover the tax penalty of this conversion.

Question - Do I need to be mindful of when I do the roth conversion? Is it okay to convert in the first quarter? even though the tax is being paid slowly over the year?

I see alot of info about scheduling an estimated payment, so not sure if I'm shooting myself in the foot by doing it this way.  Appreciate any advice.