A999 First gear engagement

In manual low the low reverse band is applied to give engine braking in first gear. Then it has to release at the same instant the second gear applies. But you probably already knew the second part.
Well I have retread the post and it sounds like this is a drag car with manual shift. No mention of brand of valve body or transbrake so we do not know if the low band is on in first in this situation. That's why I asked.