I am basically wanting to know what I should do (if anything to get a better sync speed on VDSL (Fritz 7390)) but first I will give you the story:

When I first signed up for VDSL (no POTS only VOIP) it wasn't forced (from Snap's end) to have wiring installed correctly in the house.  So I signed up and everything was great was getting sync speeds of 40000 kbit/s-42000 kbit/s down & 10000 kbit/s up.  
Upon further reading of these forums  I realised that since I didn't have wiring installed for VDSL I should at the very least disconnect all the other jack points from the demarc, which I did.  
Once I disconnected all the jack points my sync speed went up to 51000 kbit/s down & I was still on profile 8b so basically maxing out this profile which I thought was awesome.  I was then just checking my fritz every now & then to see if I would maybe get a 17a profile (as the cabinet is literally 200m down the road) but wasn't worried about it, as noted on these forums my line attenuation was probably too high (sat at around 7 or 8).  

Anyway two weeks ago my internet started bouncing so logged a job with Snap who had Chorus test the line.  Which they found to be faulty.  However the first tech from Chorus was determined that it was my wiring considering I didn't get it done in the first place.  So he played with the wiring in my house but this didn't change a thing.  To cut a long story short (after port resets and changing cards & ports at the exchange) a second Chorus tech found the line to be faulting just before it entered the house.  
He has since repaired this and cabled the house correctly - So there is now a splitter at the demarc & then CAT6 going directly to the Fritz box.  No other wiring in any other form is connected.  After a couple of days my sync is now at 44000 kbit/s-46000 kbit/s down & 10000 kbit/s up.  
My Line attenuation is down to either 5 or 6 & I have had much fewer errors which is great.  

I have upgrade to OS6 on the fritz box & had no issues.  I have also downgraded to 84.05.22 & sync speed is no different so since I had no issues I have gone back to OS6.

However back to my original question what do I need to do to (if anything or is it just time) get myself back to syncing above 50000 kbit/sm & hopefully onto a 17a profile considering I am very close to the exchange & cabling is now all correct?  Both Chorus techs said I should be at the very least syncing at 50000 kbit/s.

Appreciate the response.