Silky, OK, you've lost me. You said:
"Some of the Canaries Islands are very affected by this limit, even the newer A5 powered A320 cannot make it non stop to the UK"
What A5 engine? And which Canary Islands are you talking about? The only one I can think of where you might be performance limited is perhaps Lanzarote 03 with a strong tailwind, you would have a large weight decrement for this. But if that were the case you would use runway 21.
I have never known of an occasion where a tech stop was required for an Airbus from the Canaries to the UK.
I think all the Canary Island airports have a runway you can use from either end.
Please give us more information.