Accidentally set lights to 16/8

hello all, bit of a cock up, I spaced and set my light schedule for 16/8. They seem to be doing just fine, I am a week or two away from 12/12. Does it matter much, is it worth switching to 18/6? what problems may I get? Maybe slower growing? Cheers

I run my veg @ 18/6 all the time, nothing wrong with the size.

wont hurt a thing.The Ayahasca purple I'm growing now preferd 16 1/2 hours of light over 18 if your worried you said a week or 2 just go 2. as long as their looking good that's what matters.