Just paid to switch from entry sub to standard, and paid for 180 days.

Didn't receive any vet rewards in moogle mail and Tonberry is constantly locked down with character restrictions.
So effectively I paid Square Enix for something that they are not providing.

Any suggestions how to get hold of some support from them?

This is of no use:
Temporary Phone Support Line – (+44) 0870 600 0182 open 9:00 to 15:00(GMT)
*This temporary phone support line will be available on Saturday 26th and Sunday 27th Apr. from 9:00 to 15:00(GMT) in English only.