The dreaded passagio

In my singing, I have my passagio which is the transition area between the vocal registers, from my chest voice to my head voice at A4. With that I find it so hard to sing and lead worship songs in church because songs are usually in and around my passagio. I am quite okay in my transitions but if the phrase begins or ends with a A4, I find so hard to bring it out nicely. 

I had a one and a half hours practice in church today and by the time I sang all that time in my lower range, I could no longer sing the anthem song, one which I have picked in my higher range. I only hope I don't stretch my voice in the lower range this Sunday so I could actually sing the anthem. 

I pray I will be able to sing the song well so that the people will only hear the words and the song, and be ministered by it. 

pearlie