I really would suggest removing the plants by digging deep under them carefully & adding perlite as drainage is quite clearly an issue and is highly likely for most if not all of your problems & the perlite would go a long way to curing this, yes it is a slight risk and could even take them 2-3 days to recover but then they will be far better off.
2-3 hours hard graft and small bit of risk for much improved drainage and yield.
With the heat you need to water quite a bit but this will prevent you from doing that, not good!
Also I don't know about Norfolk's weather but here it has been over 30c and your alot lot more south than I & they are in a green house, this shouts out to me possible heat stress which again in conjunction with the drainage issue would possibly cause yellowing/dead parts or stuff that looks like nute burn all to the untrained eye.
How good is the ventilation/air flow? If possible open any vents & stuff to max and ideally stick in a couple of fans via extension from nearest power source.
All that said, they look healthy on the whole & growing well so despite what you could/should do , probably no need to be too concerned & most of us do have our issues with outdoor plants at one point or another but most will make it to the end, just with a reduced yield/potency.
Up to you MGK but the extra effort & expense could go along way to solving the issues & improve yield tons.
Hopefully this helps.
-herb
