My "plan B" - if my EVSE Upgrade'd unit can't be further upgraded to 16A L1 charging - is this unit I purchased which should arrive today:https://www.amazon.com/gp/product/B077VWBCJ4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
I would then trade/sell my upgraded unit for a stock EVSE and keep the stock Nissan EVSE at home for 12A charging and carry the 16A unit with me to work for 16A charging. This would actually be nice in a way, as I wouldn't have to constantly be unplugging/transporting/plugging-in a single EVSE. Plus, I'd have to constantly be reprogramming the charging rate on my upgraded EVSE from 16A at work down to 12A at home.
When I had my '13 EVSE upgraded back in '14 I had it upgraded to 20a L2, and assumed L1 would be 16a. Unfortunately that was not the case and it would only go up to 12a max. I called EVSEupgrade and they said all that would be required to be able to charge at 16a 120v was to purchase their 20a 120v to L6-30 adapter cable. They said they'd then give me the sequence to unlocking the 120v to 16a. Truthfully if I had known this from the beginning I would have paid the $20?? for the cable and had it included with my returned upgraded EVSE. As it was they wanted to charge another $8.95(or whatever it was, which I thought was high for such a little cable) because the cable wasn't ordered when I had my EVSE upgraded. I explained if
I had known at the time it wasn't going to go up to 16a 120v I would have ordered the cable, but no one told me and their website didn't make it clear.
I wasn't too happy with how the whole thing went down and since I already had a EVSE that went up to 16a and more @ 120v, I just dropped it. Like you?? I have the opportunity to charge at work on a rather robust 20a circuit so I wanted to take advantage of as much current as I could. In the end I ended up using a EVSE where I could set the 120v charging at 18a and never had a problem. It's a dedicated outlet and I generally only charged for an hour or two max at a time and while things get warm, they never get hot nor have I ever blown a breaker.
Don't get me wrong, I was happy with the EVSEupgrade people and their quality, I just wasn't too happy about having to pay for something I already had(a 20a 120v to 240v adapter cable) and a code I should have been given with my $300 upgrade.
Let us know how it works out, if you have the L6-30 upgrade(which it sounds like you do) I believe all they'll make you do is pay for the converter cable and shipping to you(should be less than $30). I wish you luck with your other EVSE, I have one similar and it indeed charges at 16a on both 120v and 240v but note you can't dial it down. IOW plugging it into a 15a outlet will blow your breaker, for that reason I'd not have that be my only EVSE in the car as if you need to charge somewhere you only have access to 15a, you won't be able to
I don't believe you said, but you do have a post '12 Leaf with the 6.6kw charger don't you? If not(a S model without the charger package) you'll be limited by your car's charger to 12a @ 120v and 16a @ 240v, no matter how large a EVSE you have