Actually I screwed up in calculating the tide. You want to reach Reedy Point at high tide but not earlier. You need a logarithmic equation to calculate that from 45nm away, based on the canal current which will run in access of 5 knots at times. I took a guesstimated average speed for the trip and since I didn't achieve that speed earlier well guess what I'm not here in time for the tide
The bang head is very appropriate as that is what I am doing against the current which has just gone past slack and will be ebbing soon.