Can i still top the main stem

Hi there, I would still top that plant as long as it's still in the vegetative stage for a week or longer! And don't worry about losing bud sites she will put her growth energy to the lower branches and increase the yield! You will actually increase the amount of bud sites by topping her. You also have the choice of doing some low-stress training instead. This will increase your yields by opening up the canopy to those lower bud sites. I can't tell by your diaries but if it is an auto I would recommend the low stress training over the topping. ☺️