You can. You can either re-declare a new full one to six up to and including 37, or replace individual riders like for like. 

Doyle or Bewley + AN Other?

I always thought that if you redeclare you can go to 37 for the 6 riders so if we want to replace Lawson and Scott, add the remaining 4 together so say 23 points then you can use the remaining 14 points in which ever combination you like. But I may be wrong. 

I make it 12.91 for a general double change (taking off the 0.65 we are above the limit) otherwise yes would have to be 2 individual changes like you say

We were talking about potential replacements last night Charles Wright and Jeppesen were the best we could come up with unless the Polish connection can produce someone

No licence for public use as stadium, is a likely reason.