Does an Aussie applying for a Thai visa extension based on marriage need to get his marriage certificate translated and certified for each extension?

An Aussie friend of mine, who is married to a Thai in Aussie applied for a visa ext. based on a spouse, in this process he had his Aussie marriage certificate translated at the Aussie embassy in Thailand and certified. He then got a kor 22 from the amphur office. The question is does he need get a fresh translation and certification every extension? Or only the once? Unfortunately, he gave the original in with his first extension so whatever he does he will need to do it again. KR Colin