Rossco,
I suffered with your problem for a long long time and it only got worse, to the point where I couldn't even reach my anchor. I'm still in the process of fixing it but I have made much progress. It sounds like you may be in the early stages of target panic. The earlier you beat it, the better
For myself, I don't care how long I hold as long as I reach my anchor, line things up, and pull through the shot with upper back tension.
Here is how I came around: I think of shooting my bow the same way I shoot a rifle or pistol. Think for a second about shooting a rifle. You don't even consider squeezing the trigger until the stock is on your shoulder and the sights are lined up. Think of your bow the same way. Don't even think about releasing until you've reached your anchor point and you've lined up the arrow with your intended target.
I practiced this a couple months without giving a HOOT about where my arrows went, only that I reached my anchor and got things lined up. And I thought of my bow as gun the whole time.
I got through it about year ago and have since moved on to trying to perfect my form, concentrating on using upper back tension and pulling through the shot.
Forget that it is a bow and think of it as a rifle and see what happens. It worked for me, it may or may not work for you. Good luck