The options, maximum entry ages and maximum age limits will vary between individual policies and insurers – both inside super and outside. Each policy should be considered on its own merits. Typically, cover options generally become more limited after age 59 or 60 (and there are some limitations more broadly with insurance held inside super).
If you're planning on working beyond age 65 it's preferable to check your cover as soon as possible and see if you're still protected beyond that age.