Riding solo means you can save a bit of time, my experience is that when a group stops for fuel you lose about 30 mins by the time averyone gets through having a chat/ piss/etc.
On that tank range the only time you should need to stop is when you need fuel so do it all in one go. Carry some body fuel with you so that when you stop for petrol you can make use of available toilets, have your snack and drink by the bike and you are off again very quickly.
We all think we are fast but you would be surprised at the average speed calculated at the end of the day. I did 470 mls last year to the Pyrenees after leaving San Malo at 8.30am we arrived at 7pm, ok we stopped for lunch and is was a big group so maybe i could have got there by 5pm on my own.
Remember that it's good to have an idea of how far you want to get but it all goes pear shaped if in your haste to go fast you actually go the wrong way and add 50 miles to the trip - i don't use GPS, still relying on maps.
Get to a suitable place for accommodation early evening. Nothing worse than trying to find somewhere to sleep when it's getting late and increasingly likely that it is going to be a case of under a hedge somewhere.
Hotels seem to notice that you are getting desperate and review their prices - upwards.
I do like to book in advance to set my target and know i have a bed for the night.