My son wears that type of contact lens, which works great by the way. We called Concorde this morning. The woman there told us not to worry about the 6 week/90 day conflict. Either schedule now and stay active, or have your package become inactive and then activate it after you schedule farther out.
Then I called the optometrist who will perform the exam. He thinks there is no medical basis for waiting 90 days. The intent is for your cornea to return to its "normal" shape before the exam. He said this will happen within a week or so. (My own optometrist confirmed this. In fact she told my son that he could skip wearing them for a day or two, but no more than that.) I'm not sure if they are also tested with corrective lenses on. (The CRT type lenses don't work that way.) If so, he can get tested with his natural 20/30 vision or we have to buy glasses, which he wouldn't need otherwise.
The first available exam for us isn't until the middle of August, and for different reasons, my son hasn't worn his lenses in a few weeks. So it will be nearly 60 days since he last wore his lenses by the time he is examined. The examiner thinks this will be fine, so we scheduled. If we have to push it out another month, that's what we will do.
It is unfortunate that my son's vision will not be as good as it could be for all that time. My optometrist thinks things will be OK, but he will need additional checkups and possibly a new set of lenses depending upon how long he goes without them.
I would definitely recommend contacting your eye care provider before you go to far.
Hope that helps. We've just started the process and will know something more definitive in August.