All the time TT continue to support at least some of these NAV2 devices; see the current "end-of-life" list here [Only registered and activated users can see links. ] then we can continue buying maps for all of them (subject to continuing support/donations/sponsorship etc)
We already have some map subscriptions valid to Oct-18 and even a few to 2019! If you're interested in donating, even say £5-£10 or €5-€10 then please pm me. Your older One XL is worth keeping "just in case" as that too can still be used with our maps.