I just logged into an old account that had not been played with for a long time. It says my account age is 7 years, 3 months and some days. But I only have vet rewards up to year 5. And I have not claimed the year 6 or 7. Is there any reason I would not get 6 & 7 year rewards? Looks like the last time I logged into the account (probably briefly) was 492 days ago - so a little over a year.
If those 492 days was your only break, contact CS as you should be eligible for 6 and 7 years reward. IIRC before F2P you had to have an active subs to get credit for vet reward (iow account age might be differant than "veteran age" if you took some breaks before F2P)
This article on the Knowledge Base might help a bit -- if not, contacting Customer Support directly, as Ragna has suggested, is the best way to go.